By Newton's second law, the net force acting on the crate parallel to the surface is
∑ F = mg sin(10°) - 800 N = ma
where m = 500 kg is the mass of the crate and a is the acceleration.
Solve for a :
a = ((500 kg) (9.80 m/s^2) sin(10°) - 800 N) / (500 kg)
a ≈ 0.102 m/s^2
A car takes a full round of journey in a roundabout with constant speed, as the driver got confused with the route. Can we consider it as a uniform motion? Why?
Answer: The given statement is True
Explanation:
A uniform motion is defined as the motion where an object is moving at a constant speed.
A non-uniform motion is defined as the motion where an object keeps changing its position and does not move at a constant speed.
We are given:
A car takes a full round of journey in a roundabout with constant speed
As the speed remains constant in a circular path, it is considered a uniform motion.
Hence, the given statement is True
Temperature of substance changes from -20 celsius to 20 celsius. What is temperature change in kelvin scale
Answer:
313kelvin
Explanation:
40 degree celcius plus 273=313K
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
In this experiment, the ______ was intentionally manipulated. This was the independent variable.
A. fan speed
B. mass
C. acceleration
Answer:
Fan speed
Explanation:
because is the dependent variable
Mr. Tolman believes that our universe is expanding, but with all of the gravitational force from the celestial bodies of space, the universe will begin to contract. He believes in the _____.
A) oscillating universe theory
B) inflation theory
C) steady state theory
D) big bang theory
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
10.
You are standing on a sheet of ice that covers the football stadium parking lot in Buffalo; there is
negligible friction between your feet and the ice. A friend throws you a 0.4 kg ball that is traveling
horizontally at 10 m/s. Your mass is 70 kg. If you catch the ball, with what speed do you and the ball
move afterwards?
1.02 m/s
0.06 m/s
0.02 m/s
0.12 m/s
Answer:
Explanation:
This is a classic Law of Momentum Conservation problem. For us the equation will look like this:
[tex][(m_yv_y+m_bv_b)]_b=[(m_y+m_b)v_{both}]_a[/tex] Filling in with our given info:
[tex][(70.0)(0)+(.40)(10.0)]_b=[(70.0+.40)v_{both}]_a[/tex] and
4.0 = 70.4v and
v = .06 m/s
You throw a water balloon straight up with a velocity of 13 m/s. What is its
maximum height?
O A. 4.4 m
B. 6.3 m
C. 10.7 m
D. 8.6 m
Answer:
Explanation:
[tex]h=-v^2 /2g[/tex]
[tex]with\\g = 9,8 m/s^2 or 10 m/s^2[/tex]
[tex]h= (-13)^2 / 2 * 9,8 = 8,6[/tex]
.If a vehicle covers 3 km in 5 minutes, calculate the speed of the vehicle? (With process )
Answer:
Speed = 1.6 m/s
Explanation:
Formula,
Speed = Distance ÷ Time
A exerted by an object on another is a force
hope this helps
Answer:
If a person is pushing a desk across the room, then there is an applied force acting upon the object. The applied force is the force exerted on the desk by the person.
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.
VI. A student attaches four drawing pins to a copper rod using candle wax as shown in the diagram
The rod is then heated continuously at one end and the pins fall off in the order 4, 3, 2, 1
Explanation:
[tex]C.) \: Conduction \: \\ \\ = > it \: is \: a \: process \: of \: transferring \: \\ \\ of \: heat \: from \: one \: object \: to \: another \\ \\ when \: they \: are \: in \: contact \: [/tex]
By the conduction process the heat reaches the pin.Option C is correct.
What is heat transfer?The term "heat transfer" refers to the movement of heat. The flow of heat across a system's boundary is due to a temperature differential between the system and its surroundings.
Conduction is the type of heat transfer occurs mainly in solid or by contact.In the given condition the rod is then heated continuously at one end and the pins fall off in the order 4, 3, 2, 1.
By the conduction process the heat reaches the pin.
Hence option C is correct.
To learn more about the heat transfer refer to the link;
https://brainly.com/question/13433948
#SPJ2
15. You are watching a baseball game on television that 15
being broadcast from 4500 km away. The batter hits
the ball with a loud "crack" of the bat. A microphone
is located 22 m from the batter, and you are 2.0 m from
the television set. On a day when sound travels 343 m/s
in air, what is the minimum time it takes for you to hear
the crack of the bat after the batter hits the ball?
Answer:
t_total = 6.99 s
Explanation:
It asks us how long it takes to hear the sound, for this we must look for the time (t₁) it takes for the sound to reach the microphone, the time it takes for the video signal (t₂) to reach the television and the time (₃) it takes for the TV sound to reach us, so the total delay time is
t_total = t₁ + t₂ + t₂
we look for t1, it indicates that the distance x = 22m
v = x / t
t = x / v
t₁ = 22/343
t₁ = 6.41 10-2 s
time t₂
t₂ = 4500 103/3 108
t₂ = 1.5 10-5 s
time t₃
t₃ = 2/343
t₃ = 5.83 10⁻³
Total time is
t_total = t₁ + t₂ + t₃
t_total = 6.41 10⁻² + 1.5 10⁻⁵ + 0.583 10⁻²
t_total = 6.99 s
Complete the equation to show the radioactive decay of carbon-14 to nitrogen-14
Answer:
The beta decay takes place.
Explanation:
The reaction of radioactivity of carbon 14 to nitrogen 14 is
There is a beta decay.
The reaction is
[tex]C_{6}^{14}\rightarrow N_{7}^{14}+\beta _{-1}^{0}+ energy[/tex]
Here some energy is released in form of neutrino.
which type of material is the best sound absorber?
a. glass
b. wood
c. concrete
d. carpet
Explanation:
Glass is the best sound absorber material.
1o4 Fahrenheit is equal to
Answer:
40 degrees Celsius
Explanation:
Have a great summer :)
Find the acceleration a body whose velocity increases from 11m/s to 33m/s in 10 seconds
Answer:
I am not sure if this is the answer
acceleration: 2.2m/s
Explanation:
here
initial velocity(u): 11m/s
Final velocity(v): 33m/s
time taken(t): 10 s
now
a:v-u/t
or
acceleration:final velocity-initial velocity/time taken
or
a: 33-11/10
or
a:22/10, divide it
: a=2.2m/s#
A 1500 kg truck travelling north at 60 km/hr collides with a 1200 kg car moving east at 15km/hr. If the two cars remain locked together after impact, with what velocity do they move immediately after the collision.
Answer:
33.33j+6.67i km/hr
Explanation:
From the law of conservation of momentum,
Applying,
mu+m'u' = V(m+m')............... Equation 1
Where m = mass of the truck, m' = mass of the car, u = initial velocity of the truck, u' = initial velocity of the car, V = Final velocity.
Note: let j represent the north, and i represent the east
From the question,
Given: m = 1500 kg, u = 60j, m' = 1200 kg, u' = 15i
Substitute these values into equation 1
1500*60j+1200*15i = V(1500+1200)
90000j+18000i = 2700V
V = (90000j+18000i)/2700
V = 33.33j+6.67i km/hr
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]
a body of mass 5kg moving on a horizontal ground has a coefficient of friction 0.36.find the normal reaction acting on the body?
Answer:
50 N.
Explanation:
From the question given above, the following data were obtained:
Mass (m) = 5 Kg
Coefficient of friction (μ) = 0.36
Normal reaction (N) =?
Next, we shall determine the weight of the body. This can be obtained as follow:
Mass (m) = 5 Kg
Acceleration due to gravity (g) = 10 m/s²
Weight (W) =?
W = mg
W = 5 × 10
W = 50 N
Finally, we shall determine the normal reaction. This can be obtained as follow:
Weight (W) = 50 N
Normal reaction (N) =?
Normal reaction = weight of the body
N = W = 50 N
Thus, the normal reaction acting on the body is 50 N
The switch is released and the door locks. Explain in detail how this happens.
Answer:
The iron bolt is attracted to the electromagnet. The force of attraction between the electromagnet's core and the iron bolt is greater than the force of the spring, so the iron bolt is pulled out of its housing in the door
Explanation:
A force of 20000N acts on the raft in the direction down
State the name given to the force shown by arrow in Fig.
Calculate the mass of the raft.
Answer:
Figure is not there
Explanation:
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
what is fundamental
Fundamental
forming a necessary base or core; of central importance.
"the protection of fundamental human rights"
What are the poles of a bar magnet.is it North West South or east.
Answer:
One end of any bar magnet will always want to point north if it is freely suspended. This is called the north-seeking pole of the magnet, or simply the north pole. The opposite end is called the south pole.
Explanation:
Answer:
North Pole and South Poles
Explanation:
There is no east or west in a magnetic field of a magnet. The magnetic field lines comes from North pole to south pole.
The initial momentum of a system is measured at 300 kg•m/s. Afterwards, the
momentum is measured to be 280 kg•m/s. What is the impulse of the system?
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:
Two friends are working out together using weights:
-James lifts 20kg weights up at a velocity of 1.9m/s
-Kayla lifts 15kg weights up at a velocity of 2.6m/s
0
Which friend is creating more momentum?
Answer:
Kayla. You can calculate it using the formula for momentum: momentum=mass×velocity and find the bigger number between the two momentums
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]
B
oc
OD
A metal has a specific heat capacity of 360J/(kg°C).
An object made of this metal has a mass of 2.0kg.
What is the thermal capacity (heat capacity) of the object?
Answer:
Thermal capacity of the object = 720 j/°C
Explanation:
Given:
Specific heat capacity of metal = 360J/(kg°C)
Mass of given object = 2 kg
Find:
Thermal capacity of the object
Computation:
Thermal capacity = Specific heat x Mass
Thermal capacity of the object = Specific heat capacity of metal x Mass of given object
Thermal capacity of the object = 360 x 2
Thermal capacity of the object = 720 j/°C
