A child's toy rake is held so that its output arm is 0.75 meters. If the mechanical advantage is 0.33, what is

the input arm length?

How can you increase the intensity of sound waves

A sled starts atop a hill at rest with 3,000 J of potential energy relative to the bottom of the hill. When the sled reaches the bottom of the hill it has 2,000 J of kinetic energy.

Which of the following devices is made of two different metals and produces a voltage when the metals are exposed to heat? A. An accelerometer B. A photovoltaic cell C. A crystal D. A thermocouple

A ball (mass 0.40 kg) is initially moving to the left at 30 m/s. After hitting the wall, the ball is moving to the right at 20 m/s. What is the impulse of the net force on the ball during its collision with the wall? A) 20 kg.

An 8.0 cm diameter, 400 g sphere is released from rest ta the tip of a 2.1 m long, 25 degree incline. It rolls, without slipping, to the bottom.

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?

Why does a dog circle its bed before lying down

5. Which answer correctly summarizes the essential elements of a scientific theory?. A. descriptions of the natural world; based on many observations and data; do not explain why. B.

Light can travel through a medium, but it does not require a medium. a. True b. False