Why are all machines not 100% efficient

A. Mass

B. Gravity

C. Friction

D. Distance

How does folding change rock layers

If a car is moving to the left with constant velocity, one can conclude that If a car is moving to the left with constant velocity, one can conclude that there must be no forces applied to the car.

11. How many times could Haley fly between the two flowers in 1 minute (60 seconds) ?

Discuss the validity of extrapolating the acceleration value to an angle of 90°.

A rabbit is hopping towards a clover patch. It has energy. The rabbit weighs 1kg and hops with a velocity of 20 m/s, calculate the rabbit's kinetic energy.

A pilot flies horizontally at 1300 km/h, at height h! 35 m above initially level ground. However, at time t! 0, the pilot begins to fly over ground sloping upward at angle u! 4.3° (Fig. 2-38).

A helicopter flies 30 km 30 degrees north of east, drops of the supplies to a research team; it then heads 50 degrees north of west traveling 70 km to drop the supplies to a filming crew. What is the resultant displacement of the helicopter?

Plaskett's binary system consists of two stars that revolve in a circular orbit about a center of mass midway between them. This statement implies that the masses of the two stars are equal (see figure below).

Is mercury (the planet) rocky or gaseous (meaning relating to or having the characteristics of a gas.)

What does one prolonged blast emitted by boat a using an efficient sound producing device indicate?