Why does sandpaper get hot when it is rubbed against rusty metal?

An alarm clock draws 0.7 A of current when connected to a 120 volt circuit. Calculate it's resistance

A car traveled 330 miles in 6 hours. What is the average speed?

What quantity can you calculate if you know that a car travels 30 km inn 20 minutes?

You quickly flick a limp jump rope that is held firmly by a friend at the other end. What happens? The up-and-down movement of your hand creates a longitudinal wave. The up-and-down movement of your hand creates a transverse wave.

An element's atomic number is 92. How many protons would an atom of this element have?

An electric motor rotating a workshop grinding wheel at a rate of 151 rev/min is switched off. Assume constant angular deceleration of magnitude 2.23 rad/s 2. Through how many revolutions does the wheel turn before it finally comes to rest

1. What is the atomic number of an atom? Why is this number important? |

The car travels down the road at 60mph for 1.5 hours. How far does it go?

You are riding in an elevator on the way to the eighteenthfloor of your dormitory. The elevator is accelerating upwardwith a = 1.90 m/s2. Beside you is the boxcontaining your new computer; box and contents have a total mass28.0 kg.

Why is chopping carrots a physical change?