Energy waves moving through the air

Three people, John, Paul, and George, stand on top of Garage A to carry out a physics experiment by tossing tennis balls off the top level. All three throw the tennis balls with the same speed, but in different directions.

The fossil record suggests that the first animals to evolve lived A.) in the air B.) in swamps C.) on land D.) in the sea

Which has the most kinetic energy from its motion? a) a 1,100-kg car traveling 60 km/h b) a 300-kg motorcycle traveling 100 km/h c) a 900-kg car traveling 80 km/h d) a 2,000-kg truck traveling 50 km/h

A 0.540-kg bucket rests on a scale. Into this bucket you pour sand at the constant rate of 56.0 g/s. If the sand lands in the bucket with a speed of 3.20 m/s, (a) what is the reading of the scale when there is 0.

What sound signal tells a river lock attendant that you wish to go through the lock?

Determine the power input for a motor necessary to lift 300 lb at a constant rate of 7 ft/s. the efficiency of the motor is ϵ = 0.65.

The thermal contact resistance at the interface of two 1-cm thick copper plates is measured to be 0.000056 m2K/W.

A provides resistance in an electric circuit. a. wire b. light bulb c. switch. d. battry

Why is it good for scientist to be skeptical

Which of the following describes a scientific law? A. based of scientific evidence B. explains how and why nature does what it does C. not based of scientific evidence