2. A 4-kg gun shoots a 0.1-kg bullet at 400 m/s. Find the recoil speed of the gun.

Why there is only 0.1% of the energy remaining at the 4th level of the pyramid of energy

Five hundred joules of heat are added to a closed system. The initial internal energy of the system is 87 J, and the final internal energy is 134 J. How much work is being done by the system? 221 J 279 J 366 J 453 J

Two astronomers are discussing supernovas. Dr. Frank says, "Research has established that if a supernova occurs within ten light-years of the Earth, then life on Earth will be destroyed." Dr.

Omar wrote a hypothesis about batteries called dry cells. If more dry cells are connected end to end, a light bulb will work longer because there is more energy available.

Remote controls enable users to adjust the volume and channel of televisions without having to touch the television. Which of these best describes the signals sent by remote controls to televisions?

How are mass and weight different? a. Mass is the space an object takes up and weight is the effect of gravity on mass. b. Mass is the amount of matter and weight is the effect of gravity on mass. c.

What were the discoveries of astronomers like Copernicus and Galileo?

A major obstacle to developing good human relations is that

4.) An apartment building is on fire and a guy is trapped on the fire escape ladder. There is a dumpster that is 6.3m away and is filled full of trash, and he is 7m above it.

Calculate the temperature of and power-per-area radiated from a blackbody if the spectral intensity density peaks at (a) gamma rays, λ = 1.50*10-14 m; (b) x rays, 1.50 nm; (c) red light, 640 nm; (d) broadcast television waves, 1.