Ch. 4 Practice Quiz: Multiple Choice
A man with a normal weight of 800 N stands at rest on two bathroom scales so that his weight is distributed evenly over both scales. The reading on each scale is a) 200 N b) 400 N c) 800 N d) 1600 N
b
A skydiver, who weighs 500 N, reaches terminal velocity at 90 km/hr. The force of air resistance on the skydiver upon reaching this terminal velocity is a) 0 N b) 90 N c) 410 N d) 500 N e) 590 N
d
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. Falling through the air, which person will reach a state of zero acceleration first? a) the light woman b) the heavy man c) neither... they reach it at the same time
a
An apple has a normal weight of 1 N. When held by your hand at rest above your head, the net force on the apple is a) 0 N b) 0.1 N c) 1 N d) 9.8 N e) none of these
a
An object maintains its state of motion (or lack thereof) because it possesses a) mass b) weight c) speed d) acceleration e) none of these
a
Object A has twice as much mass as Object B. Object A also has twice as much a) inertia b) velocity c) gravitational acceleration d) volume e) all of these
a
A rhinoceros pushes an elephant across a grassy savannah at a constant velocity. The elephant is sliding across the savannah as a result of the rhino's push. If the rhino pushes with a constant force of 350 N, then the sliding friction of the savannah's surface must be a) greater than 350 N b) equal to 350 N c) less than 350 N
b
A skydiver jumps from a high-flying plane through the atmosphere (without opening her parachute). As her velocity of fall increases, her acceleration a) increases b) decreases c) remains unchanged regardless of air resistance d) is equal to zero
b
An object weighs 30 N on earth. A second object weighs 30 N on the moon. Which has the greater mass? a) the one on earth b) the one on the moon c) they have the same mass d) not enough information to say
b
Ignoring any external retarding forces (e.g., friction, air resistance), if the mass of an object does not change, a constant net force on the object produces a constant a) velocity b) acceleration c) both a & b d) neither a nor b
b
Two objects of the same size (i.e., same surface area), but unequal weights, are dropped from a VERY, VERY TALL CLIFF. Assume the objects do not change physical orientation to the ground as they fall. Falling through the air, the object that hits the ground first will be the a) lighter object b) heavier object c) neither... both will hit at the same time d)...well, we can't say... not enough information
b
When a falling object has reached its terminal velocity, its acceleration is a) constant b) zero c) equal to g
b
Whenever the net external force acting on a buffalo is zero, its acceleration a) may be zero b) is zero
b
A kilogram is a measure of an object's a) weight b) force c) mass d) gravity
c
An apple has a normal weight of 1 N. The magnitude of the net force on the apple when it is in free fall is a) 0 N b) 0.1 N c) 1 N d) 9.8 N e) none of these
c
Compared to the mass of a certain object on earth, the mass of the same object on the moon is a) less b) more c) the same
c
When do you have zero acceleration? a) when you are at rest b) when you are moving at constant velocity c) both situations described in A & B d) neither situation described in A & B
c
A cheetah accelerates uniformly from 15 m/s to 45 m/s in 5 seconds Its average velocity during this time interval is a) 6 m/s b) 12 m/s c) 30 m/s d) impossible to determine from this data
c (Vavg = Vi + Vf/2)
A big bag of groceries from Harris Teeter is resting on your kitchen counter. Its mass is 10 kg. The force of gravity acting on the bag of groceries is ABOUT a) -1 N b) -10 N c) -100 N d) -1000 N
c (use Fg = mg)
A tow truck exerts a constant force of 3000 N on a car with a mass of 1500 kg. What is the acceleration of the car (in m/s/s)? a) 0.5 b) 1 c) 2 d) 4500 e) none of these values
c (use fnet = ma)