Efficiency of a machine = (useful output energy) / (total input energy)
Efficiency = (500 J output work) / (Carlotta's 2,000 J input work)
Efficiency = (500 J) / (2,000 J)
Efficiency = 0.25
<em>Efficiency = 25%</em>
-- Whether an object floats or sinks in water depends on whether its density is more or less than the density of water.
-- The density of the rock didn't change when she threw it into the lake.
-- The density of the water didn't change when she threw the rock into the lake.
-- The density of anything never depends on how much of it you have.
-- If the rock sank in two ounces of water, it'll sink in a billion gallons of water.
-- Choose ' <em>A </em>' .
Answer:
100 mph
Explanation:
Average speed = distance / time
v = 250 mi / 2.5 hr
v = 100 mi/hr
Answer:N=322.53 rpm
Explanation:
Given
Linear velocity (v)=1.25 m/s
Position from center is 3.7 cm
we know
and 
N=322.53 rpm
