Physics Questions Please Help and Explain and show steps!!!!?
1.) A diver drops from a board 10.0m above the water's surface. Find the diver's speed 5.00m above the water's surface. The find the diver's speed just before striking the water.
2.) A 1.0X10^3 kg elevator carries a max. load of 800.0 kg. A constant frictional force of 4.0X10^3 N retards the elevator's motion upward. What minimum power, in kilowatts, must the motor deliver to lift the fully loaded elevator at a constant speed of 3.00 m/s?
3.) A car w/ mass of 1.50X10^3 kg starts from rest and accelerates to a speed of 18.0 m/s in 12.0 seconds. Assume that the force of resistance remains constant at 400.0 N during this time. What is the average power developed by the car's engine?
4.)A 63.0 kg astronaut is on a spacewalk when the tether line to the shuttle breaks. The astronaut is able to throw a 10.0 kg oxygen tank in a direction away from the shuttle with a speed of 12.0 m/s, propelling the astronaut back to the shuttle. Assuming that the astronaut starts from rest, find the final speed of the astronaut after throwing the tank.
5.) An 85.0 kg fisherman jumps from a dock into a 135.0 kg rowboat at rest on the west side of the dock. If the velocity of the fisherman is 4.30 m/s to the west as he leaves the dock, what is the final velocity of the fisherman and the boat?
6.) A 0.25 kg arrow with a velocity of 12 m/s tot he west strikes and pierces the center of a kg target.
a.) What is the final velocity of the combined mass?
b.) What is the decrease in kinetic energy during the collision?
7.) A 0.015 kg marble sliding to the right at 22.5 cm/s on a frictionless surface makes an elastic head-on collision with a 0.015 kg marble moving to the left at 18.0 cm/s.
a.) Find the velocity of the second marble after the collision.
b.) Verify your answer by calculating the total kinetic energy before and after the collision.
Please answer as many as possible! Please also explain how you got your answers and show the steps! I can understand when it is explained. my teacher is very good at expaining things, so i really need help! Thanks!
