physics quiz chapter 2
A 1-kg mass at Earth's surface weighs about how many N?
10 N
The gain in speed each second for a freely falling object is about
10 m/s
Disregarding air drag, how fast must you toss a ball straight upward in order for the ball toremain in the air for a total time of 2 s
10 ms/s
If a rocket initially at rest accelerates at a rate of 50 m/s2 for 2, its speed will be
100 m/s
Ten seconds after starting from rest, a freely falling object on Earth will have a speed of about
100 m/s
The force of friction on a sliding object is 10 N. The applied force needed to maintain a constant velocity is
10N
A ball is thrown upward and then falls the same distance back to the Earth. It takes 5 seconds to reach the maximum height. Neglecting air resistance, its total time in the air is about
10s
It takes 5 s for a stone to fall to the bottom of a mine shaft. How deep is the shaft
125 m
If a ball being thrown goes from zero to 30 m/s in 1 s, what is its average acceleration
30 m/s
A man weighing 800 N stands at rest on two bathroom scales so that his weight is distributedevenly over both scales. The reading on each scale.
400 N.
An object is pulled northward with a force of 10 N and southward with a force of 15 N. Themagnitude of the net force on the object
5 N
weight of a person on Earth is 500 N. What is the msweight of a person on Earth is 500 N. What is the mass
50 kg
5 second after starting from rest, a freely falling object will have a speed of about
50 m/s
The average speed of a horse that gallops a distance of 10 km in a time of 2h is
5km/h
A ball is thrown upward with a speed of 50 m/s. How many seconds will it take to reach 0m/s at maximum height?
5s
If a car increases its velocity from zero to 60 km/h in 10 s, its acceleration is
6 km/h ∙ s
A car accelerates from rest at 2 m/s2. What is its speed 3 s after the car starts moving
6 m/s
An object is in free fall. At one instant, it travels at a speed of 50 m/s. Exactly 1 s later, its speed is about
60 m/s
The scientist to first introduce the concept of inertia was
Galileo
When you stand at rest on a pair of bathroom scales, the readings on the scales will always
add to equal your weight
Which has zero acceleration
an object at rest, an object moving at constant velocity, an object in mechanical equilibrium
An object in mechanical equilibrium is an object
at rest, moving with constant velocity, or having no acceleration
When a loaf of bread rises, its density
decreases
A ball tossed vertically upward rises, reaches its highest point, and then falls back to itsstarting point. During this time, the acceleration of the ball is always
directed downward
The two measurements necessary for calculating average speed are
distance and time
Hang from a pair of gym rings and the upward support forces of the rings will always
each be half your weight
Aristotle relied on logic in explaining nature, Galileo relied on
experiment
If a freely falling object were somehow equipped with an odometer to measure the distance it travels, then the amount of distance it travels each succeeding second would be
greater than the second before
Compared with a 1-kg block of solid iron, a 2-kg block of solid iron has twice as much
inertia mass volume
One object has twice as much mass as another object, and also has twice as much what
inertia.
Whenever the net force on an object is zero, its acceleration
is zero
A kilogram is a measure of an object's
mass
Density is the ratio of what?
mass to volume
Where is friction most evident
on a road
weight is
the gravitational attraction between you and the Earth
An object weighs 30 N on Earth. A second object weighs 30 N on the Moon. Which has thegreater mass?
the one on the Moon
Compared with the mass of a certain object on Earth, the mass of the same object on the moon
the same
Which direction does a table push a book resting on
up
As an object freely falls, its
velocity increases
When can an object be in a state of equilibrium
when two or more forces are acting on it and net force is zero
What is the acceleration of a car that maintains a constant velocity of 100 km/h for 10s
zero m/s^2