Conceptual Physics (TESC) Chapter 2
Hang from a pair of gym rings and the upward support forces of the rings will always
Add up to equal your weight
When you stand at rest on a pair of bathroom scales, the readings on the scales will always
Add up to equal your weight
The force of friction on a sliding object is 10 N. The applied force needed to maintain a constant velocity is
10 N
A 300-Kg bear grasping a vertical tree slides down at a constant velocity. The friction force between the tree and the bear is
3000N
A man weighing 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
400 N
An object is mechanical equilibrium is an object
At rest; Moving with constant velocity; and Having no acceleration
If no external forces are acting on a moving object, it will
Continue moving at the same velocity
The scientist to first introduce the concept of inertia was
Galileo
If your automobile runs out of fuel while you are driving, the engine stops but you do not come to an abrupt stop. The concept that most explains why is
Inertia
When a rocket ship accelerating in outer space runs out of fuel, it
No longer accelerates
A package fall off a truck that is moving at 30 m/s. Neglecting air resistance, the horizontal speed of the package just before it hits the ground is
about 30 m/s
Galileo's use of inclined planes allowed him to effectively
Slow down the acceleration of free fall
A sheet of paper can be withdrawn from under a container of milk without toppling it if the paper jerked quickly. This best demonstrates that
The milk carton has inertia
Galileo's interpretation of motion differed from Aristotle's in that Galileo emphasized
Time rates
According to Newton's law of inertia, a railroad train in motion should continue going forever even if its engine is turned off. We never observe this because railroad trains
Always have forces that oppose their motion
A truck is moving at constant velocity. Inside the storage compartment, a rock is dropped from the midpoint of the ceiling and strikes the floor below. The rock hits the floor
Exactly below the midpoint of the ceiling
Aristotle relied on logic in explaining nature, Galileo relied on
Experiment
Whirl a rock at the end of a string and it follows a circular path. If the string breaks, the tendency of the rock is to
Follow a straight-line path
