Answer: 27 joules
Explanation:
Work is done when force is applied on the bench over a distance. it is measured in joules.
Workdone = force x distance
= 45 N x 0.6 metres
= 27 joules
Thus, 27 joules of work is done on the bench.
The velocity of the ball when it reaches the ground is equal to B. 68.6 m/s. This value was obtained from the formula Vf = Vi + at. Vf is the final velocity. Vi is the initial velocity. The acceleration is "a", while the time of travel is "t". The solution is:
<span>Vf = Vi + at
</span>Vf = 0 + (-9.8 m/s^2) (7 s)
Vf = -68.6 m/s
The negative sign denotes the direction of the ball.
Answer:
about 4.74 seconds
Explanation:
The time to fall distance d from height h is given by ...
t = √(2d/g)
t = √(2·110 m/(9.8 m/s^2)) ≈ 4.74 s
It will take the car about 4.74 seconds to fall 110 meters to the river.
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We assume the car's speed is horizontal, so does not add or subtract anything to/from the time to fall from the height.
Answer:
Explanation:
Block A sits on block B and force is applied on block A . Block A will experience two forces 1) force P and 2 ) friction force in opposite direction of motion . Block B will experience one force that is force of friction in the direction of motion .
Let force on block A be P . friction force on it will be equal to kinetic friction, that is μ mg , where μ is coefficient of friction and m is mass of block A
friction force = .4 x 2.5 x 9.8
= 9.8 N
net force on block A = P - 9.8
acceleration = ( P - 9.8 ) / 2.5
force on block B = 9.8
acceleration = force / mass
= 9.8 / 6
for common acceleration
( P - 9.8 ) / 2.5 = 9.8 / 6
( P - 9.8 ) / 2.5 = 1.63333
P = 13.88 N .
