Chapter 6 Physics Test
A 7 N falling object encounters 7 N of air resistance. the magnitude of the net force on the object is
0 N
A box of supplies weighs 50 N when held at rest in your hands the net force on the box of supplies is
0 N
When an object reaches terminal velocity its acceleration is
0 m/s
An apple weighs 1 N. The net force on the apple when it is in free fall is
1 N
When a woman stands with two feet on a scale, the scale reads 460 N. When she lifts one foot, the scale reads
460 N
A toybox is dragged without acceleration in a straight line path across a level surface by a force of 5 N. what is the frictional force between the toybox and the surface
5 N
a 13 N falling object encounters 8 N of air resistance. the magnitude of the net force on the object is
5 N
Which of the following would exert the most pressure on the ground
A woman standing in high-heel shoes
Suppose a cart is being moved by a force. If suddenly a load is dumped into the cart so that the cart's mass doubles, what happens to the cart's acceleration?
It halves
the pascal is a unit of force
false
the speed of an object dropped in air will continue to increase without limit
false
Pressure is defined as
force per area
Accelerations are produced by
forces
If a truck has ten times the mass of a car and the two vehicles are pushed with an equal force, you would expect the acceleration of the truck to be
1/10 times that of the car
If shopping cart A has five times more mass in it than shopping cart B and the two carts are pushed with equal forces, you can expect the acceleration of shopping cart A to be
1/5 times that of the shopping cart B
Suppose the force of friction on a sliding object is 10N the force needed to maintain a constant velocity is ...
10 N
A 10 kg brick and a 1 kg brick book are dropped in a vacuum. the force of gravity on the 10 kg brick is
10 times as much the force on the 1 kg brick
A tow truck exerts a force of 4000 N on a car, accelerating it at 4 m/s what is the mass of the car
1000 kg
The terminal speed for a person parachuting (with the chute open) is about
15 km/h
A girl pulls on a 7-kg wagon with a constant force of 14 N. What is the wagon's acceleration?
2 m/s
If you pull horizontally on a crate with a force of 150 N and the crate doesn't move, the friction force must be 150 N. Now if you pull with 220 N so the crate slides at constant velocity, the friction force is
220 N
How much force is needed to accelerate a 4.0 kg physics book to an acceleration of 6.0 m/s
24.0 N
A jet has a mass of 20,000 kg. The thrust for each of four engines is 15,000 N. What is the jet's acceleration when taking off?
3 m/s
You pull horizontally on a 50 kg crate with a force of 350 N and the friction force on the crate is 200 N the acceleration of the crate is
3 m/s
A jumbo jet cruises at a constant velocity when the total thrust of the engines on the jet is 40000 N how much air resistance acts on the jet
40,000 N
A car has a mass of 2000 kg and accelerates at 4 m/s2. What net force is exerted on the car?
8000 N
An object has a constant mass. A constant force on the object produces constant
acceleration
The acceleration produced by a net force on an object is
all of the above
Suppose a particle is accelerated through space by a constant 10-N force. Suddenly the particle encounters a second force of 10-N in a direction opposite to that of the first force. The particle
continues at the speed it had when it encountered the second force
As a care package falls from a high-flying stationary helicopter, its velocity increases and its acceleration
decreases
Consider a ball rolling down the decreasing slope inside a semicircular bowl (the slope is steep at the top rim, gets less steep toward the bottom, and is zero (no slope) at the bottom). As the ball rolls from the rim downward toward the bottom, its rate of gaining speed...
decreases
When the angle of an incline with a block resting on it increases, the normal support force
decreases
You are on a frozen pond, and the ice starts to crack. If you lie down on the ice and begin to crawl, this will
decreases the pressure on the ice
A steel ball and a wooden ball of the same diameter are released together from the top of a tower. In the absence of air resistance they both would reach the ground at the same time. The reason for this is that the force on each ball is the same.
false
Excluding the force due to air pressure, there is only one force acting on a book lying at rest on a tabletop.
false
Pressure is defined as the force one object exerts on another object.
false
The acceleration of an object is inversely proportional to the net force acting on it
false
it is possible for an object in free fall to have zero acceleration
false
A block is at rest on an incline. the force of friction is necessary to prevent the block from sliding increases when the incline angle is
increased
How does acceleration of an object change in relation to its mass? It is
inversely proportional
If the force acting on a cart doubles, what happens to the cart's acceleration?
it doubles
A rock is thrown vertically into the air. At the very top of its trajectory the net force on it is
its weight
The unit of pressure is
newtons per square meter (or pascals)
A push on a 4 kg brick accelerates the brick/ neglecting friction, to equally accelerate a 16 kg brick one would have to push
none of the above
The reason a tennis ball and a solid steel ball will accelerate at the same rate, in the absence of air resistance, is that
the ball with the larger force also has the larger mass
A heavy person and a light person parachute together and wear the same size parachutes assuming they open their parachutes at the same time. which person reaches the ground first
the heavy person
A force of 2 N accelerates a mass of 2 kg at the rate of 1 m/s. the acceleration of a mass of 4 kg acted upon by a force of 4 N is
the same
Aunt Minnie throws a rock downward, and air resistance is negligible. Compared to a rock that is dropped, the acceleration of the rock after it is thrown is
the same
a speeding truck locks its brakes and it skids to a stop. if the trucks total mass were doubled, its skidding distance would be....
the same
A tennis ball and a solid steel ball with the same diameter are dropped at the same time which ball has the greater force acting on it
the steel ball
A tennis ball and a solid steel ball with the same diameter are dropped at the same time. Which ball has the greater ACCELERATION ?
they both have the same acceleration
A fluid can be either a liquid or a gas.
true
the combination of all the force that act on an object is called the net force
true
the net force on an objecting falling at terminal velocity is zero
true