1. The sun and other stars produce visible light by

a. fluorescence.

b. luminescence.

c. incandescence.

d. electroluminescence.

Which statements accurately describes the waste generated by nuclear reactions? check all that apply. A. It is hazardous for hundreds to thousands of years B. some waste can be recycled and used again C. it is hazardous to living organisms forever D.

Tim, with mass 53.5 kg, climbs a gymnasium rope a distance of 4.7 m. The acceleration of gravity is 9.8 m/s2. How much potential energy does Tim gain? Answer in units of J

Rosa studies the position-time graph of two race cars. Rosa concludes that truck X has a greater velocity than truck Y, and that truck Y had a head start.

A rock, which weighs 1400 n in air, has an apparent weight of 900 n when submerged in fresh water (998 kg/m3). the volume of the rock is:

A student lifts a 90 pound (lb) ball 4 feet (ft) in 5 seconds (s). How many joules of work has the student completed? A) 770J B) 369J C) 488 ft lbs D) 488.6 J

A car moving at a steady 10 m/s on a level highway encounters a bump that has a circular cross-section with a radius of 30 m. The car maintains its speed over the bump. What is the normal force exerted by the seat of the car on a 60.

Determine the magnitude of the force p required to hold the 180-kg crate in equilibrium.

Match the following: 12) Site where resistance to blood flow is greatest. 13) Site where blood pressure is lowest. 14) Site where exchanges of food and gases are made. 15) Site where the blood pressure is greatest.

How many trees were sold in all during 1999 and 2000?

a cannon sits on a stationary railroad flatcar with a total mass of 1000 kg. when a 10 kg cannonball is fired to the left at a speed of 50 m/s, what is the speed of the flatcar