At 2.5 seconds, the helicopter has a kinetic energy of 20 J. What is its mechanical energy at that time?

What is neccessary for a magnetic field to create electric current in a copper coil? a. the magnetic field must be moving or changing b. the magnetic field must not be moving c.

James wants to lower the pitch coming from an electronic sound generator. how would he achieve that? a. he should increase the amplitude. b. he should increase the frequency c. he should decrease the amplitude. d. he should decrease the frequency. e.

Tech A says that twin leading shoe brake systems are more efficient in forward braking than reverse braking. Tech B says that leading/trailing shoe brake systems provide equal, but not maximum, braking in both directions. Who is correct?

Which of the following organisms is an example of nekton?

A rock is thrown up into the air. It reaches the apex of it's flight and falls back down to the Earth. At the top of the rock's flight, what is rock's acceleration?

Which method would you use to find the volume of an irregular shaped object?

A step up transformer has a primary coil with 100 turns and a secondary coil with 25 turns if the input voltage in the primary coil is 40 volts what is the output voltage reduced to in the secondary coil A) 20 volts B) 35 volts C) 4 volts D) 10

An instrument used to measure atmospheric pressure is called a

A 200-kg boulder is 1000-m above the ground. what is its potential energy?

The law of reflection states that if the angle of incidence is 81 degrees, the angle of reflection is ___ degrees.