Answer:
a) [tex]A=5m/s^2[/tex]
b) [tex]V=25m/s[/tex]
Explanation:
From the question we are told that:
Velocity [tex]v=90km/h=25m/s[/tex]
Time [tex]t=5.0s[/tex]
a)
Generally From Newton's motion equation for Average acceleration is mathematically given by
[tex]A=\frac{V-U}{t}[/tex]
Since its from Rest Therefore
[tex]U=0[/tex]
[tex]A=\frac{25m/s-0}{5s}[/tex]
[tex]A=5m/s^2[/tex]
b)
Generally the equation for Average Velocity is mathematically given by
[tex]V=u+at[/tex]
[tex]AT t=1.0s\\\\V=0+5(1)[/tex]
[tex]V=5m/s[/tex]
[tex]AT t=2.0s\\\\V=0+5(2)[/tex]
[tex]V=10m/s[/tex]
[tex]AT t=5.0s\\\\V=0+5(5)[/tex]
[tex]V=25m/s[/tex]
What is the activity of a source that emits 1,200 particles per minute?
A. 1,200 Bq
B. 20 Bq
C. 72,000 Bq
What is the activity of a source that emits 1,200 particles per minute?
[tex]\boxed{ B. \:20 \:Bq }[/tex]
Explanation:
20 Bq is the activity of a source that emits 1,200 particles per minute. Activity is the number of decays per second. The SI unit for activity is becquerel (Bq).
[tex]\bold{ \green{ \star{ \orange{Mystique35}}}}⋆[/tex]
Answer:
B) 20 Bq
The activity of a source that emits 1,200 particles per minute is 20 Bq.
-------------------------
☆hope it helps
☆have a great day!!
describe 2 ways you could increase the efficiency of a household central heating system
Answer:
Arrange an annual service. Treat your boiler like your car. ...
Keep your boiler clean. ...
Bleed your radiators. ...
Top up the pressure. ...
Use a Powerflush. ...
Insulate your pipes. ...
Turn the heating on. ...
If all else fails…
Explanation:
If a driver makes contact with a steering wheel during a 35 mph crash, she comes to rest in about Δ=15 ms. If, during an identical crash, the driver makes contact with an air bag, she comes to rest in about Δ=110 ms. What is the ratio of the force exerted by the steering wheel to the force exerted by the air bag on the driver?
Answer:
The ratio of forces is 22 : 3.
Explanation:
Case I:
initial velocity, u = 35 mph
final velocity, v = 0
time, t = 15 ms
Case II:
initial velocity, u = 35 mph
final velocity, v = 0
time, t' = 110 ms
let the mass is m.
According to the Newton's second law, the force is given by the rate of change of momentum.
So
[tex]F =\frac{m(v-u)}{t}\\\\F'= \frac{m(v-u)}{t'}\\\\So, \frac{F}{F'} =\frac{t'}{t}\\\\\frac{F}{F'}=\frac{110}{15}=22:3[/tex]
Which of the following are correct statements about the way an atom is put
together?
Check all that apply.
A. The valence shell is the innermost shell of electrons in an atom.
B. Electrons are found in the nucleus of an atom.
O C. There are two electrons in all electron shells.
O D. Electrons are in layers around the nucleus.
***** multiple choice ******
Answer:
valenc e shell
Explanation:
The Statue of Liberty is made of Copper that has turned on Says has WAGNE Bongo Wantse
said about this change?
The change is a physical change because the owner in the same is still there,
The change is a physical change beave a new chemical is was on the outside of the sale,
The change is not a physical change beans the plos at the stanje na dana),
The change is nga physical change because a new chemical istmes on the outside of the stalye
Complete Question:
The Statue of Liberty is made of copper that has turned green because it has undergone a change. What can be said about this change?
Group of answer choices.
A. The change is a physical change because the copper in the statue is still there.
B. The change is a physical change because a new chemical is formed on the outside of the statue.
C. The change is not a physical change because the color of the statue has changed.
D. The change is not a physical change because a new chemical is formed on the outside of the statue.
Answer:
D. The change is not a physical change because a new chemical is formed on the outside of the statue.
Explanation:
A physical change can be defined as a type of change that only affects the physical form of a chemical substance (matter) without having any effect on its chemical properties. Thus, a physical change would only affect the physical appearance and properties of a chemical substance (matter) but not its chemical properties.
This ultimately implies that, a physical change result in a change of matter from one form or phase (liquid, solid or gas) to another without a corresponding change in chemical composition.
Additionally, a physical change is a type of change that involves an increase or decrease in the volume of a physical object (object). Also, this change can be reversed to the original state under certain conditions.
Since the Statue of Liberty which is made of copper turned green, the change is not a physical change because a new chemical is formed on the outside of the statue.
The chart shows data for four moving objects. Which object has the greatest acceleration?
Answer:
Y
Explanation:
Acceleration = (v-u)/t
W = (29-11)/6 = 3
X = (34-10)/12 = 2
Y = (40-12)/7 = 4
Z = (28-20)/8 = 1
So the answer is Y = 4.
Hope this will help. Please mark me brainliest.
rocks from volcanoes are used by scientists to study the interior of the earth
TRUE OR FALSE
5)
A 2.0-meter length of copper wire is connected across a potential difference of 24 millivolts.
The current through the wire is 0.40 ampere. The same copper wire at the same temperature
Is then connected across a potential difference of 48 millivolts. The current through the wire
is
A)
0.20 A
B)
0.80 A
C)
1.6 A
D)
0.40 A
Answer:
The current through the wire is equal to 0.8 A.
Explanation:
Given that,
The length of a copper wire = 2 m
Potential difference = 24 mV
The current through the wire is 0.40 A.
The new potential difference is 48 mV.
We need to find the current through the wire.
As the potential difference is doubled for second wire. So the new current will be :
I' = 2I
= 2 × 0.4
= 0.80 A
So, the current through the wire is equal to 0.8 A.
Use the equation d = st, where d = distance, s = speed, and t = time. If you jog
at a speed of 1.5 m/s for 20 seconds, how far do you travel?
A. 13.3 m
B. 30 m
C. 5 m
D. 21.5 m
Answer:
Distance = 30 meters
Explanation:
Given the following data;
Speed = 1.5 m/s
Time = 20 seconds
To find the distance travelled;
Speed can be defined as distance covered per unit time. Speed is a scalar quantity and as such it has magnitude but no direction.
Mathematically, speed is given by the formula;
[tex]Speed = \frac{distance}{time}[/tex]
Making distance the subject of formula, we have;
[tex] Distance = speed * time [/tex]
Substituting into the above formula, we have;
[tex] Distance = 1.5 * 20 [/tex]
Distance = 30 meters
Which best compares radiation and conduction?
C Both transfer thermal energy from warm objects to cooler objects.
O Both can transfer energy through empty space.
O Both transfer thermal energy by electromagnetic waves.
O Both involve the transfer of energy through direct contact.
Answer:
The statements that best compares radiation and conduction are the following: both transfer thermal energy from warm objects to cooler objects and both can transfer energy through matter. The difference is that conduction is through direct heat transfer; whereas, radiation transfers heat through waves.
A bicyclist rides 2.93 km due east, while the resistive force from the air has a magnitude of 8.65 N and points due west. The rider then turns around and rides 2.93 km due west, back to her starting point. The resistive force from the air on the return trip has a magnitude of 8.65 N and points due east. Find the work done by the resistive force during the round trip. Number Type your answer here Units Choose your answer here
Answer:
-50.6 kJ
Explanation:
The work done (W) on an object is given by:
W = (Fcosθ) * S
where F is the force, S is the displacement and θ is the angle between the force and displacement.
i) During the first trip riding east, S₁ = 2.93 km = 2930 m, F₁ = 8.65 N.
The displacement is due east and the force is due west, hence θ₁ = 180°. Therefore:
W₁ = (F₁ * cosθ₁)S₁ = (8,65 * cos(180))2930 = -25.3 kJ
ii) i) During the second trip riding west, S₂ = 2.93 km = 2930 m, F₂ = 8.65 N.
The displacement is due west and the force is due east, hence θ₂ = 180°. Therefore:
W₂ = (F₂ * cosθ₂)S₂ = (8,65 * cos(180))2930 = -25.3 kJ
work done by the resistive force during the round trip is:
W = W₁ + W₂ = -25.3 kJ + (-25.3 kJ) = -50.6 kJ
Question 3 of 5
Which term refers to a transfer of thermal energy between objects?
O A. Temperature
OB. Heat
O C. Kinetic energy
O D. Potential energy
Answer:
Heat
Explanation:
The term heat refers to the conduction process which occurs when energy is passed between objects
Answer
Heat
did quiz and got it correct
which force is responsible for the moon revolving around the sun?
Which of the following graph is used for determining the instantaneous velocity from the slope?
A. distance-time graph
B. x - t graph
C. both of these
D. none of these
Answer:
B. x - t graph
Explanation:
A position-time (x-t) graph is a graph of the position of an object against (versus) time.
Generally, the slope of the line of a position-time (x-t) graph is typically used to determine or calculate the velocity of an object.
An instantaneous velocity can be defined as the rate of change in position of an object in motion for a short-specified interval of time. Thus, an instantaneous velocity is a quantity that can be found by measuring the slope of a line that is tangent to a point on the graph.
Hence, the x - t graph also referred to as the position-time graph is used for determining the instantaneous velocity from the slope.
For example;
Given that the equation of motion is S(t) = 4t² + 2t + 10. Find the instantaneous velocity at t = 5 seconds.
Solution.
[tex] S(t) = 4t^{2} + 2t + 10[/tex]
Differentiating the equation, we have;
[tex] S(t) = 8t + 2 [/tex]
Substituting the value of "t" into the equation, we have;
[tex] S(5) = 8(5) + 2 [/tex]
[tex] S(5) = 40 + 2 [/tex]
S(5) = 42 m/s.
Answer:
B. x - t graph
Explanation:
Thus, an instantaneous velocity is a quantity that can be found by measuring the slope of a line that is tangent to a point on the graph. Hence, the x - t graph also referred to as the position-time graph is used for determining the instantaneous velocity from the slope.
hey what is magnetic field
Answer:
a region around a magnetic material or a moving electric charge within which the force of magnetism acts.
Explanation:
The definition of a magnetic field is a place in space near a magnet or an electric current where a physical field is created from a moving electric charge that creates a force on another moving electric charge. An example of a magnetic field is the Earth's magnetic field.
The isotope used to remove cancer malignancy cell the given options are a. Strontium 89 b. Uranium 238 c. Carbon 14 d. Chlorine 37.......... can anyone tell me the ans plzz
Answer:
B. Uranium 238.
Explanation:
It is radioactive and can be used to treat cancer in the form of radiotherapy
a) How much electrical energy, in joules, does a 1000W space heater consume when it runs for 8h? (b) How much energy is that in kilowatt hours? (c) Calculate the cost of using this heater if 1kWh costs 0.5 dollars.
Answer:
a. Energy = 28800000 Joules
b. Energy = 8 Kwh
c. Cost = $4
Explanation:
Given the following data;
Power = 1000 Watts
Time = 8 hours
Cost = $0.5 per KWh
Conversion:
1 hour = 60 * 60 = 3600 seconds
8 hour = 8 * 3600 = 28800 seconds
a. To find much electrical energy, in joules;
Energy = power * time
Energy = 1000 * 28800
Energy = 28800000 Joules
b. To find how much energy is that in kilowatt hours;
Energy = power * time
Energy = 1000 * 8
Energy = 8000 Watt-hour = 8000/1000 = 8 Kwh (1 Kilowatts is equal to 1000 watts).
c. To calculate the cost of using this heater;
Cost = 8 * 0.5
Cost = $4
there is no gain in mechanical advantage in a single fixed pulley but they are used
Answer:
A single fixed pulley is used to lift load by changing the direction of the lifting force. Even though a single fixed pulley has no mechanical gain in that, the effort applied is greater than the load, it is preferred in use since you do not have to pull or push the pulley up and down.
Explanation:
The answer itself speaks
Difinition of peel?and write the main point
Answer:
PEEL writing offers writers the ability to write through a structure. It helps to express your ideas and opinions to the reader in writing a PEEL paragraph.
Explanation:
PEEL writing gives your thoughts a deep perception. The writing techniques are very simple, but they can be complicated.
The Point, Evidence, Explanation and Link is an acronym for PEEL. All of them belong to the paragraph. The main way to master PEEL writing is consistent practise. You will find it very easy to learn when you understand the nature of the essay. Other important aspects of writing are planning and research.
Point:-
This is the most important, because it is the first part of the paragraph. The first sentence describes the point to be discussed in the entire paragraph. The opening phrase is the subject phrase. To make them understand the whole paragraph, the first sentence should be clear to the audience.
This section is also a key part of the essay. After you have written an analysis, you have a clear idea of what the reader can convey.
Write the equation which links gravitational potential energy,height and mass.
Answer:
PE = mgh
Explanation:
The equation of potential energy is mgh.
Gold at 100.0°C is placed in 2.00×10^2 g of water at 20.0°C. The mixture reaches equilibrium at 21.2°C. the specific heat of gold is 0.129 (J/g°C) What is the mass of the gold? Specific heat of water is 4.18 (J/g°C) .
Answer:
there it is fella atleast i tried
1) Un cuerpo se mueve desacelerando a razón de 8m/s2, calcula: a) La velocidad que tenía 5 segundos antes de detenerse. b) La distancia recorrida los últimos 5 segundos de su trayectoria.
Answer:
Initial velocity (u) = 40 m/s
Distance travel in last 5 seconds = 100 m
Explanation:
Given:
Acceleration (a) = 8 m/s²
Final velocity (v) = 0 m/s
Find;
1] Initial velocity before 5 sec
2] Distance travel in last 5 seconds
Computation:
1] Initial velocity before 5 sec
v = u + at
0 = u + (-8)(5)
u - 40 = 0
Initial velocity (u) = 40 m/s
2] Distance travel in last 5 seconds
s = ut + (1/2)(a)(t²)
s = (40)(5) + (1/2)(-8)(5²)
s = 200 - 100
Distance travel in last 5 seconds = 100 m
A 52 kg child on a swing is travelling at 6 m/s . What is his gravitational potential energy if he has 1000 J of the mechanical energy?
Answer:
The correct answer is "64 J".
Explanation:
The given values are:
Mass,
m = 52 kg
Velocity,
v = 6 m/s
Mechanical energy,
= 1000 J
Now,
The gravitational potential energy will be:
⇒ [tex]P.E=1000-\frac{1}{2}mv^2[/tex]
[tex]=1000-\frac{1}{2}\times 52\times (6)^2[/tex]
[tex]=1000-26\times 36[/tex]
[tex]=1000-936[/tex]
[tex]=64 \ J[/tex]
Calculate the man’s mass. (Use PE = m × g × h, where g = 9.8 N/kg.)
A man climbs a wall that has a height of 8.4 meters and gains a potential energy of 4,620 joules. His mass is about
kilograms
Answer:
mass=56.12kg
Explanation:
PE=mgh
4620=m×9.8×8.4
make m subject of the formula...
m =4620/(9.8×8.4)
m=4620/82.32
m=56.12kg
3 Draw energy transfer diagrams
for:
a) winding up a clockwork car
b) letting a clockwork car run
c) letting a battery-powered car
run.
Answer:
The outline of the energy transfer are;
a) Kinetic energy → Clockwork spring → Potential energy
b) Potential energy in clockwork car → Clockwork spring coil unwound → Clockwork car run
c) Chemical potential energy → Batteries in the car → Electric motors → Kinetic energy
Please find attached the drawings of the energy transfer created with MS Visio
Explanation:
The energy transfer diagrams are diagrams that can be used to indicate the part of a system where energy is stored and the form and location to which the energy is transferred
a) The energy transfer diagram for the winding up a clockwork car is given as follows;
Mechanical kinetic energy is used to wind up (turn) the clockwork car such that the kinetic energy is transformed into potential energy and stored in the wound up clockwork as follows;
Kinetic energy → Clockwork spring → Potential energy
b) Letting a wound up clockwork car run results in the conversion of mechanical potential energy into kinetic (energy due tom motion) energy as follows;
Potential energy in clockwork car → Clockwork spring coil unwound → Clockwork car run
c) The energy stored in the battery of a battery powered car is chemical potential energy. When the battery powered car runs, the chemical potential energy produces an electromotive force which is converted into kinetic energy as electric current flows from the batteries
Therefore, we have;
Chemical potential energy → Batteries in the car → Electric motors → Kinetic energy
The pressure difference, , across a partial blockage in an artery (called a stenosis) is approximated by the equation where is the blood velocity, the blood viscosity , the blood density , the artery diameter, the area of the unobstructed artery, and the area of the stenosis. Determine the dimensions of the constants and . Would this equation be valid in any system of units
The question is incomplete. The complete question is :
The pressure difference, Δp, ac[tex]K_u[/tex]ross a partial blockage in an artery (called a stenosis) is approximated by the equation :
[tex]$\Delta p=K_v\frac{\mu V}{D}+K_u\left(\frac{A_0}{A_1}-1\right)^2 \rho V^2$[/tex]
Where V is the blood velocity, μ the blood viscosity {FT/L2}, ρ the blood density {M/L3}, D the artery diameter, [tex]A_0[/tex] the area of the unobstructed artery, and A1 the area of the stenosis. Determine the dimensions of the constants [tex]K_v[/tex] and [tex]K_u[/tex]. Would this equation be valid in any system of units?
Solution :
From the dimension homogeneity, we require :
[tex]$\Delta p=K_v\frac{\mu V}{D}+K_u\left(\frac{A_0}{A_1}-1\right)^2 \rho V^2$[/tex]
Here, x means dimension of x. i.e.
[tex]$[ML^{-1}T^{-2}]=\frac{[K_v][ML^{-1}T^{-1}][LT^{-1}]}{[L]}+[K_u][1][ML^{-3}][L^2T^{-2}]$[/tex]
[tex]$=[K_v][ML^{-1}T^{-2}]+[K_u][ML^{-1}T^{-2}]$[/tex]
So, [tex]$[K_u]=[K_v]=[1 ]=$[/tex] dimensionless
So, [tex]K_u[/tex] and [tex]K_v[/tex] are dimensionless constants.
This equation will be working in any system of units. The constants [tex]K_u[/tex] and [tex]K_v[/tex] will be different for different system of units.
a car travelled at 50km/hr for 3 hours, how far did the car travel
Answer:
The answer answer is 150 km
Answer:
Explanation:
Distance =Speed×time
Speed=50km/hr
Time=3hours
Hence the Distance will be(50km/hr×3hours)
The answer is 150km
Ciara is swinging a 0.015 kg ball tied to a string around her head in a flat, horizontal circle. The radius of the circle is 0.50 m. It takes the ball 0.70 seconds to complete one full circle. Calculate the tension in the string and its direction that provides the centripetal force acting on the ball to keep it in the circular path.
A. 0.60 N, along the line tangent to the circle
B. 0.015 N, along the line tangent to the circle
C. 0.60 N, toward the center of the circle
D. 0.015 N, toward the center of the circle
Answer:
Option C
Explanation:
From the question we are told that:
Mass [tex]m=0.015kg[/tex]
Radius [tex]r=0.5m[/tex]
Time [tex]t=0.70[/tex]
Generally the equation for Tension is mathematically given by
[tex]T=\frac{4mr}{t^2} \pi[/tex]
[tex]T=\frac{4*0.015*0.5}{(0.70)^2} (3.142)[/tex]
[tex]T=0.60N[/tex]
Therefore
[tex]T=0.60 N[/tex], toward the center of the circle
Option C
Answer:
0.60 N, toward the center of the circle
Explanation:
Got it right on the test.
Directions. Read and understand each item carefully. Write your answers on the space provided.
1. Create a graphic representation based on the following data tabulated on Table 2 and make an interpretation of
the graph. Make sure to coordinate points correctly and trace line to show motion of the object.
Table 2. The distance travelled by a car in a given time.
(Dudes I need this today, pls answer this correctly)
Answer:
Please find attached the required graph of the data points
The graph can be interpreted as showing that which was at rest starts moving at a constant speed of 2 km/min
Explanation:
The table is presented as follows;
[tex]\begin{array}{lcl}Time \ (min)&& Distance \ (km)\\0&&0\\5&&10\\10&&20\\15&&30\\20&&40\\25&&50\\30&&60\end{array}[/tex]
The graphic representation of the above data can be created by plotting the Time on the x-axis and the Distance on the y-axis on a graph paper
The graph of the data can be created also using a spreadsheet application such as MS Excel by using the Chart function under the Insert menu, after selecting the points input into cells on the spreadsheet as shown in the attached drawing
The distance travelled by the car in a given time is found by obtaining the rate of change of the values of the graph, m, as follows;
[tex]m =\dfrac{y_{2}-y_{1}}{x_{2}-x_{1}}[/tex]
Where (y₁, x₁), and (x₂, y₂) are a pair of chosen points on the given line
When, the chosen points are (y₁, x₁) = (0, 0), and (x₂, y₂) = (30, 60), we get;
[tex]m =\dfrac{60 \, km-0 \, km}{30 \, min-0 \, min} = 2 \, km/min[/tex]
The graph can be interpreted as showing that the rate of change of the distance travelled by the car per unit time which is the speed of the car starting from rest is 2 km/min
Uma bola é lançada para cima com a velocidade inicial de 20m/s. A sua aceleração é constante e igual a 10m/s² para baixo. Quanto tempo permanece a bola no ar? Qual é a maior altura atingida pela bola? Quando a bola está a 15 m de altura em relação ao solo?
Answer:
sorry but i cannot understand your language, can you speak in english
