Why is the reflection of a wave at a free boundary different from reflection at a fixed boundary?

Force between two objects are being accelerated toward each other by gravitational attraction

Donelle measures the mass of 10 pennies and records her measurements in kilograms. She wants to determine the mean mass of her pennies. What should Donelle do to make it easier to calculate the mean mass of her pennies? A.

When can a truck have less momentum than a bike? A. only when the truck is not moving B. only when it's moving faster than the bike C. only when it's moving more slowly than the bike D.

Total resistance across any branch of a circuit can be found by analyzing whether the branch is connected in A. series or parallel B. sequence or series C. perpendicular or parallel D. parallel or antiparallel

A rocket, initially at rest on the ground, accelerates straight upward from rest with constant acceleration 58.8 m/s^2. The acceleration period lasts for time 8.00 s until the fuel is exhausted. After that, the rocket is in free fall.

A microwave oven operating at 120 volts is used to heat a sandwich if the oven draws 12.5 amperes of current for 45 seconds what is the power dissipated by the oven?

Which of the transformers are step-up transformers? Which of the transformers are step-down transformers?

1 A plane moving at 30m/s drops a load 200m down to the ground. How long did it take to hit the ground.

Can a body be in equilibrium if it is in motion? Explain

What is the average speed in kilometers per second of the earth around the sun?