Do sound waves must have a medium to travel but elctromagnetic waves cannot

When you cut a board with a power saw as compared with a handsaw, how much work do you do with the power saw? A. less work in less time B. the same amount of work in less time C. more work in less time D. less work in more time

Does voltage vary or the same in a series circuit

A baseball with a mass of 0.15 kilograms collides with a bat at a speed of 40 meters/second. The duration of the collision is 8.0 * 10-3 seconds. The ball moves off with a speed of 50 meters/second in the opposite direction.

Calculate the acceleration of a 2000 kg Single engine airplane just before take off one that's rest of its engine is 500 n

A proton (mass m 1.67 10 27 kg) is being accelerated along a straight line at 3.6 1015 m/s2 in a machine. If the proton has an initial speed of 2.4 107 m/s and travels 3.5 cm, what then is (a) its speed and (b) the increase in its kinetic energy

What is the equivalent resistance of a circuit that contains two 50.0 resistors connected in parallel with a 12.0 V battery? A. 100.0 B. 25.0 C. 0.040 D. 0.48

When a wave moves from a less dense medium to a denser one, most of the wave energy is refracted? A) true B) false

Describe the differences and similarities between levers and hydraulics

Much of the pollution in our oceans comes from: organic pesticides fumes and smog car exhaust sewage and industrial waste

What is the density of a sample of sulfur with a volume of 0.6cm