Calculate the amount of work done if you use a 100n force to push a 50kg box 5m across the kitchen floor.

a)
250 j

b)
500 j

c)
5000 j

d)
50,000 j

2)
tommy was walking at a rate of 4
miles
hour
at noon and at 12: 30 pm he was walking at a brisk rate of 6
miles
hour
. two hours later tommy was walking at a leisurely rate of 2
miles
hour
. which statement about tommy's accleration is true?

a)
tommy had an accleration of zero the entire time.

b)
tommy had a positive acceleration between noon and 12: 30 pm.

c)
tommy had a positive acceleration between 12: 30 and 2: 30 pm.

d)
tommy had a negative acceleration between noon and 12: 30 pm.

3)
gravity is a force between any two objects with mass. why doesn't a person feel a gravitational force between him/herself and another person?

a)
a person doesn't exert a gravitational force.

b)
the two gravitational forces cancel each other out.

c)
the gravitational forces of people is so small it is overshadowed by that of earth.

d)
there are so many people we are actually balanced by all the different gravitational forces.

4)
four wrestlers step on a scale for a tournament. wrestler a weighs in at 170 pounds; wrestler b weighs in at 168 pounds; wrestler c weighs in at 171 pounds; and wrestler d weighs in at 169 pounds. which of these wrestlers experiences the greatest force due to gravity?

a)
wrestler a

b)
wrestler b

c)
wrestler c

d)
wrestler d

5)

consider the substance represented by the heating curve. what is the most accurate conclusion can you draw about the vaporization of the substance?

a)
heat of fusion equals heat of vaporization.

b)
the melting point is half the boiling point.

c)
it takes the substance longer to vaporize than it does to condense.

d)
it requires much more energy to vaporize the substance than to melt it.

6)

which best describes the speed and velocity of the graph?

a)
both speed and velocity are changing.

b)
the speed and velocity remain constant.

c)
the speed is constant and velocity is changing.

d)
the velocity cannot be determined from the graph.

7)

at the county fair, carrie and sam climbed up on the carousel horses. around and around they went; the horses also bobbed up and down. when they got off of the carousel, carrie told sam they had been accelerating during their ride. sam disagreed; they had been moving at a constant speed. whose response is fully correct, and why?

a)
carrie is, because the carousel changed speed when it started and stopped.

b)
sam is, because the horses never moved from their position on the carousel.

c)
carrie is, because velocity includes speed plus direction, and both changed.

d)
sam is, they did not accelerate since their speed remained constant for the ride.

8)
a fan is connected to a battery in a series circuit. what kind of energy transfer occurs if the circuit is closed?

a)
light energy changes to chemical energy.

b)
thermal energy changes to mechanical energy.

c)
chemical energy changes to mechanical energy.

d)
mechanical energy changes to chemical energy.

9)

sam and sally are both running the mile at the region track meet. one mile equals four laps around the oval track. they are neck and neck during most of the race, but at the half-mile mark sam starts to pull ahead. he wins the race with a time of 5 minutes 25 seconds. sally stops at .9 miles to have a drink of water and then continues to the finish line.

how does sam and sally's displacement compare for the race?

a)
their displacement is the same, zero miles.

b)
sam's displacement is greater than sally's.

c)
sally's displacement is greater than sam's.

d)
both sam and sally's displacement is 1 mile.

10)
to lift a load of 100 kg a distance of 1 m an effort of 25 kg must be applied over an inclined plane of length 4 m. what must be done to lift the load 2 m, using the same effort?

a)
use an inclined plane of length 8 m.

b)
use an inclined plane of length 2 m.

c)
use an inclined plane of length 10 m.

d)
use an inclined plane of length 16 m.