The critical angle for total internal reflection at the boundary between an unknown substance and air is 24.4°. what is the angle of refraction in the air if light is incident on the boundary at an angle of 20.0°?

A wagon is rolling forward on level ground. friction is negligible. the person sitting in the wagon is holding a rock. the total mass of the wagon, rider, and rock is 95.5 kg. the mass of the rock is 0.290 kg.

Eardrum vibrations are transmitted to the cochlea by a piston consisting of

Which of the following is evidence of Earth's age provided by fossils? Fossils are found only in sedimentary rock. Fossils range from simple to complex across rock layers. Fossils formed gradually over time. Fossils are found in rock above water.

Consider lifting a box of mass m to a height h using two different methods: lifting the box directly or lifting the box using a pulley (as in the previous part).

Which of the following statements are true as a block of ice melts? Check all that apply. a. The temperature of the ice/water system remains constant. b. Heat energy leaves the ice/water system. c. Heat energy enters the ice/water system. d.

8. A gas is contained in a horizontal piston-cylinder apparatus at a pressure of 350 kPa and a volume of 0.02 m3. Determine the work done by the piston on the gas if the cylinder volume is increased to 0.15 m3 through heating.

A 75.0 kg person stands on a scale in an elevator. (a) What does the scale read (in N and in kg) when the elevator is at rest?

The hinge at A and cable BDC support beam ABC. Cable BDC passes over the pulley D that is pinned to the ceiling. (Assume that the + x-axis is to the right and the + y-axis is up along the page.

The "zone of avoidance" a) Accounts for the absence of any planet between the orbits of Mars and Jupiter Prevents collisions between planets in the Solar System.

Electric current is ...