A certain heat engine extracts 1.30 kJ of heat from a hot temperature reservoir and discharges 0.70 kJ of heat to a cold temperature reservoir. What is the efficiency of this engine?

Why is the density of iron higher than the density of oxygen?

An object moving with constant acceleration near the surface of the earth is influenced by

You cover 10 meters in a time of 1 second. Is your speed the same if you cover 20 meters in 2 seconds?

A rock weighing 98 newtons is pushed off the edge of a bridge 50 meters above the ground. What was the potential energy of the rock before it began to fall?

As excess carbon dioxide is stored in the atmosphere and the atmosphere warms, this heat is also transferred to what?

an electric clothes dryer has a resictance of 16 Ohms it drawes 15 A of current what is the voltage in volts of the wall outlet that it is pluged into

A lorry with a mass of 5000kg accelerates to overtake a caravan on the motorway. Its acceleration is 1.5m/s². What force must the engine be providing? You can ignore the effects of friction and air resistance

Norma kicks a soccer ball with an initial velocity of 10.0 meters per second at an angle of 30.0% if the ball moves though the air for 3.2 seconds what's the horizontal distance traveled by the ball

Suppose s (t) is the position of an object moving along a line at time t is greater than or equal to 0. What is the average velocity between the times t=a and t=b? What is the instantaneous velocity at t=a?

Estimate how long it would take one person to mow a football field using an ordinary home lawn mower. suppose that the mower moves with a 1-km/h speed, has a 0.5-m width, and a field is 360 ft long and 160 ft wide. 1 m = 3.281 ft.