01 HW

A mosquito flying at 3 m/s encounters a 3-m/s breeze blowing in the opposite direction, which gives it a resulting speed over the ground of

0 m/s

The support force on a 10-N book that rests on a horizontal surface is

10

If a freely falling object were somehow equipped with a speedometer, its speed reading would increase each second by about

10 m/s

Ten seconds after starting from rest, a freely-falling baseball will have a speed of about

100 m/s

Daisy weighs 120 N and carries Trixie who weighs 40 N on her back. The support force on Daisy's feet is

160

A 50-N object falling in air experiences 30 N of air resistance. The amount of net force on the falling object is

20

The average speed of a horse that gallops a distance of 10 km in a time of 30 min is

20 km/h

If a ball rolls down an inclined plane and gains 4 m/s each second it rolls, its acceleration is

4 m/s2

An 800-N man stands at rest with his weight evenly distributed on two bathroom scales. The reading on each scale is

400

When a 10-kg block is simultaneously pushed toward the east with 20 N and toward the west with 15 N, the combination of these forces on the block is

5 N east

An object is pulled with two forces, 10 N northward and 15 N southward. The magnitude of the net force is

5N

When a 10-N object is suspended at rest by two equally-taut vertical strands of rope, the tension in each strand is

5N

A 10-N falling object encounters 4 N of air resistance. The net force on it is

6

As an object freely falls, it's ______ increases.

Acceleration

An empty jug of weight W is at rest on a table. When water of weight w is poured into it, the amount of support force supplied by the table is

W + w.

You're at rest in a hammock when a hungry mosquito sees you as lunch, while a 2-m/s breeze is blowing. If the mosquito joins you for lunch, it should first hover over you by flying

against the breeze at 2 m/s

Which has zero acceleration?

all of the above

Given that two forces of 10 N and 15 N act horizontally (one dimension) on an object, the net force must

be either 5 N or 25 N

When sign painters Burl and Paul stand on opposite ends of a scaffold, the tensions in each of the two supporting ropes

depend on the relative weights of Burl and Paul.

Aristotle treated motion by

dividing it into two classes

When a crate slides down an incline at a constant velocity it is

dynamic equilibrium

Marie pushes horizontally on her desk, but not hard enough to get it moving. The friction force acting on the desk is

equal and opposite to her push

Burl and Paul on a sign-painting scaffold are in equilibrium, which means that the net upward supporting force of the vertical ropes is

equal and opposite to the combined weights of Burl, Paul, and the scaffold.

A motor scooter undergoes acceleration when it

gains speed, decreases speed, and changes direction

A glance at the speedometer on your vehicle will tell you your

instantaneous speed

When a ball increases in speed by the same amount each second, its acceleration

is constant

Whenever the net force on an object is zero, its acceleration

is zero

When Marie pushes her desk to the right, friction between the floor and the desk acts toward

left

A chunk of gold weighs 1 N on Earth. On the Moon its weight would be

less

A kilogram is a unit of

mass

Between mass and weight, the more fundamental quantity is

mass

The net force on an object is

the combination of all forces acting on it

Your weight is

the gravitational attraction between you and the earth

When you push a crate across a level floor at constant velocity, friction between the crate and the floor is

the same amount as your pushing force

Acceleration and velocity are

very different from each other

Acceleration and velocity are

very different from each others

Lift an object against the force of gravity if you want to judge its

weight