Answer:
72%
Calculating Efficiency:
The amount of work obtained from a machine is always less than the amount of work put into it. Thisis because some of the work is lost due to friction. The efficiency of a machine can be calculated usingthe following formula:Percent Efficiency = (work output-Machine / work input-You) x 100%
Answer:
- <u>First choice:</u><u><em> Because the mass of the cannon ball is much less than the cannon</em></u>
Explanation:
Indeed, <em>Newton's Third Law</em>, i.e. the action-reaction law, states that any action (force) will have a reaction (force) of same magnitude but opposite direction.
That means that when a cannon goes off the cannon ball exerts a force on the cannon and the cannon exerts the same force back on the cannon ball.
To find out how much the cannon ball and the cannon itsel move, you must consider Newton's second law.
- F = m×a (force equal mass times acceleration).
Clearing the acceleration you get:
Then, since the mass is in the denominator and both the force that the cannon ball exerts on the cannon and the cannon exerts on the cannon ball are equal in magnitude, then the body that has the smaller mass (the cannon ball) will experience a greater acceleration, which is stated by the first choice: because the mass of the cannon ball is much less than the cannon.
Answer:
C. Acceleration due to gravity
Explanation:
which is 9.8 m/s2 on Earth. The formula for calculating weight is F = m × 9.8 m/s2.
