1. Which of the following is an example of a second-class lever?

wheelbarrow

broom

crowbar

shovel

2. Which of the following is an example of a first-class lever?

rake

nut cracker

seesaw

elbow joint

In order to rendezvous with an asteroid passing close to the earth, a spacecraft must be moving at 8.50*103m/s relative to the earth at a distance 2.50*108m from the center of the earth.

What is the following atmospheric property associated with? sinking air heated air cooled air

Alex collides with a desk as he runs through his office. If the combined momentum of Alex and the desk was 400 kg•m/s to the north before the collision, what is their combined momentum after the collision?

Subatomic particles that do not possess any charge but provide mass to atoms are called

Which quantity is a vector? (1) power (2) kinetic energy (3) speed (4) weight

Two children pulling the rope with the same force in opposite direction is that an unbalanced force or a balanced force

During sublimation particles in a solid room deodorizer move directly into the air as a gas how does the movement of the deodorizer particles change? the particles ___.

A 50-g ball rolls across the table at 2 m/s. A 100-g ball rolls across the same table at 1 m/s. Which ball has more momentum?

The cross section area of a hole is 725cm^2. Given that the area of a circle is A=3.14r^2, find the radius of the hole.

How long does it take the moon to go from full-moon phase to new-moon phase