SCI 101 Final 1

A train reduces its velocity from 16.7 m/s to 5.56 m/s in a time of 8 seconds. Find the acceleration.

-1.37 m/s2

A 10-N falling object encounters 10 N of air resistance. The net force on it is

0 N

A 50-N object falling in air experiences 50 N of air resistance. The amount of net force on the falling object is

0 N

What is the acceleration of a car that maintains a constant velocity of 100 km/h for 10 s?

0 m/s2

When a skydiver of mass 100 kg experiences air resistance of 400 N, her acceleration is

0.6 g

A car accelerates at 2 m/s2. Assuming the car starts from rest, how much time does it need to reach a speed of 20 m/sec.

10 sec

When a baseball player hits a ball with a force of 1000 N, the ball exerts force on the bat of

1000 N

A tow truck exerts a force of 3000 N on a car that accelerates at 2 m/s2. The mass of the car must be

1500 kg

A metal body of mass 216 g occupies a volume of 80 cm3, what is the density?

2.7 g/cm3

A car has a mass of 1000 kg and accelerates at 2 m/s2. What is the magnitude of the force exerted on the car?

2000 N

If a person walked at 2 m/s for 12 seconds he would travel a distance of

24 m

If a total distance of 750 m is covered in a time interval of 25 seconds, the average speed is

30 m/s

If a Jaguar sports car accelerates from zero to 100 km/h in 3.0 s its acceleration is

33.3 km/h/s

If a jaguar sports car accelerates from zero to 100 km/sec in 3.0 sec its acceleration is

33.3 km/s

If a ball rolls down an inclined plane and picks up 4 m/s each second it rolls, its acceleration is

4 m/s2

When a 10-kg block is simultaneously pushed toward the east with 20 N and toward the west with 15 N, the combination of these forces on the block is

5 N East

Nellie runs the length of a 100 yard football field in a time of 20 seconds. Her average running speed is

5 yards/sec

An African elephant can reach heights of over 13 feet and possess a mass of 6000 kg. Determine the weight of the elephant.

58800 N

A 10 N falling object encounters 4 N of air resistance. The net force on it is

6 N

An object in free fall has a speed of 60 m/s. One second later its speed is

70 m/s

A 2400 kg truck accelerates from 5 m/s to 45 m/s in 10 sec. The next force on the truck is

9600 N

A pair of tennis balls fall through the air from a tall building. One ball is regular and the other is filled with lead pellets. The ball to reach the ground first is the

Lead filled ball

Action and reaction forces comprise the parts of

a single interaction

If the mass of an object does not change, a constant net force on the object produces constant

acceleration

Which has zero acceleration?

an object in mechanical equilibrium, an object moving at constant velocity, an object at rest (all of the above)

Which has the greatest mass?

automobile battery

A given net force propels an object along a straight-line path by a force. If the mass were doubled, its acceleration would

be half

To steadily (constantly) increase the velocity of something requires a

constant force

When an object falls through the air and gains velocity, the net force actually

decreases

When an object falls through the air, as velocity increases its acceleration

decreases

A tutor will be correct in saying that velocity and acceleration are

different concepts

The two measurements necessary for calculating average speed are

distance and time

A given net force propels an object along a straight-line path. If the net force were doubled, its acceleration would

double

A parachutist falling at constant velocity is in a state of

dynamic equilibrium

Inside the interior of a truck that moves at constant velocity is a package that drops from the midpoint of the ceiling. The package hits the floor

exactly below the midpoint of the ceiling.

During each second of free fall, the speed of an object

increases by the same amount

Whenever the net force on an object is zero, its acceleration

is zero

Galileo said that if you rolled a ball along a level surface it would

keep rolling without slowing down if no friction acted upon it.

A kilogram is a measure of an object's

mass

A ball is thrown vertically into the air. Because of air resistance, its time coming down compared to its time going up is

more

While a car travels around a circular track at constant speed, its

none of the above

The equilibrium rule (sigma F=0) applies to

objects or systems at rest & objects or systems in uniform motion in a straight line (both)

A rock is thrown vertically upward. At the top of its straight-line path the force acting on it is

only the force due to gravity

A heavy rock and a light rock in free fall have the same acceleration. Both rocks have the same acceleration because

ratio of force to mass is the same

The force exerted on the tires of a car to directly accelerate it along a road is exerted by the

road

The resistive force of friction occurs for

solids, liquids, & gases (all of the above)

When you push your desk to the right, friction on the desk acts toward

the left

What did Galileo incorporate in his study of motion that Aristotle overlooked?

the role of time

A force of 1 N accelerates a 1-kg mass at 1 m/s2. The acceleration of a 2-kg mass acted upon by a force of 2 N is

the same

The speed of a vertically-thrown ball at the top of its path is

zero