N/A — Exam Answers

50 verified answers
23

A student wants to determine the impulse delivered to the lab cart when it runs into the wall. The student measures the mass of the cart and the velocity of the cart before it hits the wall. What other measurement is necessary to calculate the impulse delivered to the lab cart?

A
the velocity of the cart after it hits the wall
B
the time the cart is in contact with the wall
C
the acceleration of the cart before it hits the wall
D
the force exerted on the cart by the wall
24

A hot air balloon pilot wants the balloon to quickly rise several feet higher so it will be above some trees in the distance. Which best explains how the pilot can make the balloon rise?

A
The pilot can increase the temperature inside the balloon so it is warmer than the surrounding air.
B
The pilot can adjust the density of the air inside the balloon so it is equal to the density of the surrounding air.
C
The pilot can decrease the temperature inside the balloon so it is cooler than the surrounding air.
D
The pilot can adjust the temperature inside the balloon so it is equal to the temperature of the surrounding air.
28

Which statements describe the motion of a planet according to Kepler’s second law? Choose two correct answers.

A
A planet’s orbit is an ellipse with the Sun at one focus.
B
The speed of a planet varies as it moves in its orbit.
C
A planet sweeps out an equal area in equal units of time.
D
A planet’s orbit is a circle centered on the Sun.
E
A planet travels the same distance along its orbit in equal units of time.
F
The speed of a planet is constant as it moves in its orbit.
30

Which is an example of conduction?

A
A hand is burned when touching a pot handle.
B
A stone gets hot from sitting outside on a sunny day.
C
Air above an ocean warms up and rises.
D
Soup is warmed in a microwave oven.
31

What is the approximate tangential speed of an object orbiting Earth with a radius of 1 point 8 times 10 to the 8th power m and a period of 2 point 2 times 10 to the 4th power s ?

A
5 point 1 times 10 to the 4th power m/s
B
7 point 7 times 10 to the 4th power m/s
C
7 point 7 times 10 to the negative 4 power m/s
D
5 point 1 times 10 to the 5th power m/s
32

In which scenario is the greatest amount of work done on a wagon?

A
A force of 40 N moves it 10 m.
B
A force of 60 N moves it 6 m.
C
A force of 50 N moves it 5 m.
D
A force of 55 N moves it 8 m.
35

Which is the best example of kinetic energy?

A
Image with description A picture of an owl sitting on a branch.
B
Image with description A picture of some rocks sitting on grass.
C
Image with description A picture of a field of flowers in the sunlight.
D
Image with description A picture of a dog running.
37

A car moving south speeds up from 10 meters per second to 40 meters per second in 15 seconds. What is the car’s acceleration?

A
2 the fraction with numerator m and denominator s squared
B
15 the fraction with numerator m and denominator s squared
C
30 the fraction with numerator m and denominator s squared
D
50 the fraction with numerator m and denominator s squared
38

Describe the shape of liquid water as it is poured into a glass.

A
The shape changes and continues to change long after pouring stops.
B
The shape stays the same, and the shape of the glass changes.
C
The shape stays the same as it was before it was poured.
D
The shape changes to fit the glass and then stays the same.
39

If all else stays the same, which change could be made to cause an increase in the gravitational force on a space shuttle?

A
decreasing the distance of the space shuttle from Earth
B
increasing the distance of the space shuttle from Earth
C
increasing the universal gravitational constant acting on the space shuttle
D
decreasing the universal gravitational constant acting on the space shuttle
40

When a baseball player catches a baseball, the glove "gives" or moves backward. How does this movement affect the change in momentum of the baseball?

A
The change in momentum stays the same because the ball still comes to a stop.
B
The change in momentum depends on the initial speed of the ball and the time to stop.
C
The change in momentum increases because the impact time increases.
D
The change in momentum decreases because the force decreases.

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