How does friction affect a machine efficiency?

A child and sled with a combined mass of 50.0 kg slide down a frictionless slope. if the sled starts from rest and has a speed of 4.00 m/s at the bottom, what is the height of the hill? m

the air pressure in a car is 210kPa at a temperature of 26°C. What is the temperature of the air in the tyre of the pressure of 220kPa? [assume that the volume of the air in the tyre is constant]

You throw a 5.5 g coin straight down at 4.0 m/s from a 25-m-high bridge. A) How much work does gravity do as the coin falls to the water below? B) What is the speed of the coin just as it hits the water?

4) Company A believes that electric cars are the future of the automotive industry. Which of these factors would prohibit Company A from developing this idea further? A) The new electric car would be less expensive to the consumer.

Dave's sister gets very stressed out during final exam time; however, Dave isn't affected by the stress. What does this illustrate? A. Fight or flight response B. Personal stress C. Relaxation response D. Subjective stress

What does sound travel throu better

How does a change in resistance affect the conductivity of a material? A) The lower the resistance, the worse the conductivity B) The lower the resistance, the better the conductivity C) The higher the resistance, the better the conductivity D) The

Two railroad cars, each of mass 6500 kg and traveling 80 km/h in opposite directions, collide head-on and come to rest. how much thermal energy is produced in this collision?

What is a result of using a machine?

A boy rides motorbike with velocity of 20 m/s He accelerates his motorbike to a velocity of 30 m/s for 5 second. Calculate the acceleration produced in the motorbike. [Ams 2ms