Andrea rides her bicycle at a speed of 10 m/s. She and the bike have a combined mass of
50 kg.
a.
If she uses her brakes to slow down to 5 m/s, how much energy is converted to
heat?
Answer:
1875 J of energy is converted to heat.
Explanation:
Given that,
The combined mass of Andrea and the bike is 50 kg
Initial speed of Andrea's bicycle, u = 10 m/s
Final speed of Andrea's bicycle, v = 5 m/s
The energy converted to heat can be calculated using the work-energy theorem as follows :
[tex]E=\dfrac{1}{2}m(v^2-u^2)\\\\E=\dfrac{1}{2}\times 50\times ((5)^2-(10)^2)\\\\E=-1875\ J[/tex]
So, 1875 J of energy is converted to heat.
Help me frfr I don’t understand
The points are
(1,10)
(6,0)
[tex]\boxed{\sf slope(m)=\dfrac{y_2-y_1}{x_2-x_1}}[/tex]
[tex]\\ \sf\longmapsto m=\dfrac{0-10}{6-1}[/tex]
[tex]\\ \sf\longmapsto m=\dfrac{-10}{5}[/tex]
[tex]\\ \sf\longmapsto m=-2[/tex]
A girl walks 55 m downhill in 3.2 s. What is her average velocity?
Answer:
V = 17.2
Explanation:
Speed = distance(m) / time(s)
= 55m / 3.2s
=17.2 m/s
Which is an outer planet?
Answer:
pluto
Explanation:
Dwarf because it is very minut
Answer:
I think Saturn.
Explanation:
I think the inner planets are Mercury, Venus, Earth and Mars whereas the outer ones are Jupiter, Saturn, Uranus and Neptune.
Enlight the contribution of science and technology for current pandemic of Corona virus??
The vaccine ofcourse. They helped in making the vaccine.
what is momentum
what is momentum in words
Answer:
It's a strength or force
Explanation:
the quantity of motion of a moving body, measured as a product of its mass and velocity
Answer:
momentum is a quality define as the product of the mass and velocity of an object.
The gravitational force of the two objects is 6.67x10-11N. Explain this statement.
Answer:
it means that the force of attraction between two object in gravitation is 6.67×10-11N
It means that the force of attraction between two object in gravitation is 6.67×10-11N.
What is the formula of mass in gravitational force?The formula is g = GM/r2, Where M is the mass of the Earth, r is the radius of the Earth (or distance between the center of the Earth and you, standing on its surface), and G is the gravitational constant. G (without the subscripts) is the gravitational constant, and c is the speed of light.
What is the gravitational force between two objects?The gravitational force between two objects is proportional to their masses and inversely proportional to the square of the distance between their centers. joining the two centers of masses.
Learn more about gravitational force here: brainly.com/question/13010127
#SPJ2
A hockey puck has a mass of 0.21 kg. If the hockey puck
is moving with 74 J of kinetic energy, what is its speed?
Show all your work.
Answer:
v = 26.54 m/s
Explanation:
Given that,
The mass of a hockey puck, m = 0.21 kg
The kinetic energy of the hockey puck, E= 74 J
We need to find the speed of the hockey puck. Let the speed is v. We know that, the kinetic energy is given by :
[tex]E=\dfrac{1}{2}mv^2[/tex]
Where
v is the speed
So,
[tex]v=\sqrt{\dfrac{2E}{m}} \\\\v=\sqrt{\dfrac{2\times 74}{0.21}} \\\\v=26.54\ m/s[/tex]
So, the speed of the hockey puck is 26.54 m/s.
state any two effects of gravitational force
Answer:
The effect of gravity extends from each object out into space in all directions, and for an infinite distance. However, the strength of the gravitational force reduces quickly with distance. Humans are never aware of the Sun's gravity pulling them because the pull is so small at the distance between the Earth and Sun.
Answer:
The Earth's gravitational force accelerates objects when they fall. It constantly pulls, and the objects constantly speed up.
Explanation:
Las carreras de velocidad pura en el atletismo son:
A. Un ladrón perseguido por la policia
B.100 y 200 mts planos
C. salir corriendo cuando la mama lo va a castigar
D.N.A
What's energy band theory???
Answer:
Energy band theory is a basis for describing processes and effects in solid crystals under electromagnetic field impact.
Explanation:
Single atoms have a discrete energy spectrum, which means they can occupy only discrete energy levels. Part of these energy levels are filled with electrons in a non-excited condition. Part of these levels can be occupied only when electrons are excited.
Tính công của dòng điện
Answer:
CG gh sure er go b vh pxuh FPI OO c AM h kh
Please help!! :)
For this circuit, what will be the voltage drop across R1?
A. 21.3 V
B. 14.2 V
C. 45.0 V
D. 9.47 V
Answer:
Option D. 9.47 V
Explanation:
We'll begin by calculating the equivalent resistance of the circuit. This can be obtained as follow:
Resistor 1 (R₁) = 20 Ω
Resistor 2 (R₂) = 30 Ω
Resistor 3 (R₃) = 45 Ω
Equivalent Resistance (R) =?
R = R₁ + R₂ + R₃ (series connections)
R = 20 + 30 + 45
R = 95 Ω
Next, we shall determine the current in the circuit. This can be obtained as follow:
Voltage (V) = 45 V
Equivalent Resistance (R) = 95 Ω
Current (I) =?
V = IR
45 = I × 95
Divide both side by 95
I = 45 / 95
I = 0.4737 A
Finally, we shall determine, the voltage across R₁. This can be obtained as follow:
NOTE: Since the resistors are in series connection, the same current will pass through them.
Current (I) = 0.4737 A
Resistor 1 (R₁) = 20 Ω
Voltage 1 (V₁) =?
V₁ = IR₁
V₁ = 0.4737 × 20
V₁ = 9.47 V
Therefore, the voltage across R₁ is 9.47 V.
Answer:
9.47
Explanation:
Just Took the Test
State any ten reasons why students in Uganda need to study physics?use examples of the possible technological advancements which can be made using the knowledge of physics
Answer:
1.it also hleps us to became doctors becuase without physics you can't be a doctor
2.physics needs to be steady whether you like it or not it helps you in life so everybody must study physics no matter is in Uganda USA and plenty more countries there must be physics to dare to be studied
A train 90m long stops in a train station with its front buffers in line with a lamp post on the platform. Later it starts off with an average acceleration of 0.45m/s. What will be its speed in kilometers per hour when the tail buffers pass the lamp post P?
Answer:
The speed of the train when the tail buffers pass the lamp post is 9 m/s
Explanation:
The given parameters are;
The length of the train = 90 m
The initial velocity of the train, u = 0
The average acceleration of the train, a = 0.45 m/s²
When the tail buffer pass the lamp post, P, we have;
The distance travelled, s = The length of the train = 90 m
The kinematic equation of motion is given as follows;
v² = u² + 2·a·s
Where;
v = The speed of the train when the tail buffers pass the lamp post
∴ v² = 0² + 2 × 0.45 m/s² × 90 m = 81 m²/s²
Therefore;
v = √(81 m²/s²) = 9 m/s
The speed of the train when the tail buffers pass the lamp post, v = 9 m/s.
Why is it difficult to maintain constant speed of a vehicle?
Answer:
The road surface is always rough, so the frictional force between the tires and the road surface make it difficult to maintain constant speed because acceleration always changes.
The eficiency of a
simple machine can never be 100% why?
Answer:
Systems always tend toward a state of decreasing order unless more energy is provided into the system to counteract this tendency.
experiment to calculate the spring constant of a spring.
on
when you throw a ball
the
ground
and it
bounces back to your hand,
is it elastic collision ? Explain.
Answer:
The ground hits the ball with same force with which the balls hit the ground. That's why ball bounces back.
Gravity stops it from bouncing forever.
Hope this helps..
help with this physics question please :)
Answer:
is that rm in you profile pic
An iron weight, suspended by a string, is motionless. The tension
in the string is 4.75 newtons. What is the mass of the iron
weight?
Answer:
Explanation:
If the mass hangs at the end of the string and the string can support the mass and doesn't break, and the mass hangs still, that means that the tension in the string is equal to the downward pull of the mass. However, we are given the tension in Newtons and the mass needs to be in kg. So we use the equation for weight:
w = mg where w, the weight, is the same as the tension in the string. Gravity is always 9.8 in the metric system:
4.75 = m(9.8) so
m = .48 kg
Answer:
Answer: A
0.485 Kg
Explanation:
A girl is travelling on her bike at a speed 2.59 m/s. If the
girl and her bike have a kinetic energy of 190 J, what is
the combined mass of the girl and her bike? Show all
your work
Answer:
Mass, m = 146.72 kilograms
Explanation:
Given the following data;
Kinetic energy = 190 J
Velocity = 2.59 m/s
To find the combined mass of the girl and her bike;
Kinetic energy can be defined as an energy possessed by an object or body due to its motion.
Mathematically, kinetic energy is given by the formula;
K.E = ½mv²
Where;
K.E represents kinetic energy measured in Joules.
M represents mass measured in kilograms.
V represents velocity measured in metres per seconds square.
190 = ½*m*2.59
Cross-multiplying, we have:
380 = 2.59m
Mass, m = 380/2.59
Mass, m = 146.72 kilograms
numerical filing method is more scientific why give me 4 reason
Answer:
Numerical Methods are mathematical way to solve certain problems.Whether the equations are linear or nonlinear, efficient and robust numerical methods are required to solve the system of algebraic equations.
Analytical solutions are exact solutions based on mathematical principles.
However, the governing partial differential equations of fluid flow are complex and cannot be solved by analytical means. The partial differential equations are therefore converted into a system of algebraic equations that are subsequently solved through numerical methods to provide approximate solutions to the governing equations.
Although we rarely reach on exact answer , we can get really close to the exact answer much quicker than solve analytically.
Answer:
oh my god
Explanation:
how long answer is this
Write down the role played by four digestive juices in digestion and the
organs which secrete them.
Answer:
Digestive juices secreted by various organs such as salivary glands in the mouth, stomach, liver and pancreas help in the process of digestion of food. Saliva secreted by the salivary glands in the mouth aids in the breakdown of starch present in the food to simple sugar
Explanation:
Define measurement with examples.
Explanation:
Measurement is defined as the act of measuring or the size of something. An example of measurement means the use of a ruler to determine the length of a piece of paper. An example of measurement is 15" by 25". ... The dimension, quantity, or capacity determined by measuring.
Measurement refers to the comparison of unknown physical quantity with a known quantity.
for eg. measurement of body while sewing clothes.......
Quả bóng 200g chuyển động với v 4m/s đập vào tường rồi bật ra ngược chiều với cùng tốc độ độ biến thiên động lượng của quả bóng là
Two rams run toward each other. One ram has a mass of 44 kg and runs south with a speed of 6 m/s, while the other has a mass of 50 kg and runs north with a speed of 3 m/s. What will the momentum of the system made up of the two rams be after they collide? Assume the total momentum of the system is conserved.
A. 114 kg-m/s south
B. 414 kg-m/s south
C. 414 kg m/s north
D. 114 kg-m/s north
the torque produced in a body is equal to the product of one of the force and the _______
(a) couple
(b) force
(c) like parallel force
(d) couple arm
An object of mass 10 kg has a momentum of 15 kg m/s. Find the average force required to accelerate the object to 10 m/s over 20 seconds.
Answer:
Force = 4.25 Newton
Explanation:
Given the following data;
Mass = 10 kg
Momentum = 15 Kgm/s
Time, t = 20 seconds
Final velocity, V = 10 m/s
To find the average force required;
First of all, we would determine the initial velocity of the object.
Momentum = mass * velocity
15 = 10 * velocity
Velocity = 15/10
Velocity = 1.5 m/s
Next, we would determine the acceleration of the object by using the first equation of motion;
V = U + at
10 = 1.5 + a*20
10 - 1.5 = 20a
8.5 = 20a
Acceleration, a = 8.5/20
Acceleration, a = 0.425 m/s²
Lastly, we would find the average force by using the formula;
Force = mass * acceleration
Force = 10 * 0.425
Force = 4.25 Newton
20. A semiconductor is a
crystalline solid that conducts current under any condition
metallic solid that conducts current under any condition
metallic solid that conducts current under certain conditions
crystalline solid that conducts current under certain conditions
Answer:
D. crystalline solid that conducts current under certain conditions
Explanation:
Semiconductors are crystalline solids that has the ability to conduct electrical currents but on certain conditions e.g heat. The conduction of semiconductors is less than that of conductors (metals) but more than insulators (nonmetals), hence, they are said to be intermediates of conductors and insulators in terms of electrical conductivity.
Examples of semiconductors are silicon, boron, carbon, germanium, arsenic etc.
