36 terms

# Exam 2

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the gravitational attraction force between you and the Earth
A peice of rope is pulled by two people in a game of tug-of-war. each pulls with 400 N of force. What is the tension in the rope
400 N
A tow truck exerts a force of 3000 N on a car, accelerating it at 2 meters per second. What is the mass of the car
1500 kg
you ride an elevator that is moving with constant upward acceleration while standing on a bathroom scale. The reading on the scale is
more than your true weight, mg
an objects weight may properly be expressed in units of
newtons
a skydiver who weighs 500 N, reaches terminal velocity of 90 km/h. the air resistance on the diver is then
500 N
the force exerted on the tires of a car to directly accelerate it along a road is exerted by the
a person is attracted toward the center of earth by a 500 N gravitaional force. The earth is attracted toward the person with a force of
500 N
A force is a vector quantity because is has both
magnitude and direction
a skydiver jumps from a high-flying plane. as her velocity of fall increases, the acceleration
decreases
which of the following is not a vector quantity?
speed, acceleration, velocity
speed
if an objects mass is decreasing while a constant force is applied to the object the acceleration
increases
the force required to maintain an object at a constant velocity in free space is equal to
zero.
as a car drives with its tires rolling freely without any slippage, the type of friction acting between the tires and the road is
static friction
when a falling object has reached its terminal velocity, its acceleration is
zero
a cocnut and a feather fall from a tree though the air to the ground below. The amount of air-resistance froce is greater on
the coconut
a push on a 1-kg brick accelerates it. Neglecting friction, to equally accelerate a 10-kg brick, one would have to push with
10 times as much force
when a falling object has reached its terminal velocity, its acceleration is
zero
if an 18-wheeler and a toyota corolla have a head on collision, which vehicle will experience the greater change in velocity?
toyota corolla
arnold strongman and suzie small each pull very hard on opposite ends of a massless rope in a tug of war. the greater force on the rope is exerted by:
both the same, interestingly enough
a skydivers terminal velocity will be greatest if she falls
a 10 N falling object encounters 4 N of air resistance. The net force on the object is
6 N.
a gun fires a bullet. does the gun or the bullet experience a greater force, and which of newtons 3 laws explains this fact?
the gun and the bullet experience the same force as a consequence of newtons 3rd law.
Which has zero acceleration?
at rest
in mechanical equilibrium
moving at constant velocity
all of these
which of the following represents an action/reaction pair?
the force of shoes pushing on the ground and the force of the ground pushing back on the shoes as a person is in the process of jumping.
if a non-rotating object as no acceleration, then we can say for certain that it is
in mechinical equilibrium
a player catches a ball. consider the action force to be the impact of the ball against the player's glove. the reaction to this force is the
force the glove exerts on the ball
two tennis balls fall through the air from a tall building. one of them is filled with lead pellets. the ball to first reach the ground is the
is a sky-siver wgi gas reached terminal speed in free fall?
no
a 10 kg brick and a 1 kg book are dropped in a vaccuum. The force of gravity on the 10kg brick is
10 times as much
a plane flied east 300 km for 1.00 hr, then turns north and continues another 300 km from 1.00 hr. what direction was the average acceleration of the plane?
north west
a 20 ton truck collides with a 1500 lb car and causes a lot of damage to the car.
the force of the collision on the truck is equal to the force of collision on the car.
consider the foces acting on a dog standing stationary waiting for a treat, namely the force of gravity acting down and the upward support of the floor. Do these two forces form an action reaction pair?
no
strange as it may seem, it is just as hard to accelerate a car on a level surface on the moon as it is here on the earth. this is because
the mass of the car is independent gravity
a light woman and a heavy man jump from an airplane at the same time and open their same-size parachutes at the same time. which person will get to a state of zero acceleration first?
the light woman.
a 16 kg fish is weighed with two spring scales, each of negligible weight. what will be the reading on the scales?
the sum of the two readings will be 32 kg.