Answer: 2.21 m/s
Explanation:
Given
Coin reaches a height of 0.25 m above the launch point
Suppose u is the initial speed of the coin
Using the equation of motion
Putting values
Thus, the initial velocity is 2.21 m/s
From first law of motion, law of inertia, we know that an object remains in the state of rest or motion unless acted upon by an unbalanced external force. The skateboard riding down a hill when reaches the bottom slows down due to <u>frictional force </u>acting in the opposite direction. Frictional force is a contact force which acts between two surfaces against the direction of motion of one surface over the other. Here, frictional force acts <u>between skateboard and ground</u>. This reduces the speed of the skateboard and it eventually stops.
Answer:
D
Explanation
take 5x2000 and J is the unit for power therfore it cant be A and B and C are not 10,000.
The faster car behind is catching up/closing the gap/gaining on
the slow truck in front at the rate of (90 - 50) = 40 km/hr.
At that rate, it takes (100 m) / (40,000 m/hr) = 1/400 of an hour
to reach the truck.
(1/400 hour) x (3,600 seconds/hour) = 3600/400 = <em>9 seconds</em>, exactly
