We know, U = mgh
Substitute the known values,
19.6 = m * 9.8 * 8
m = 19.6 / 78.4
m = 1/4
In short, Your Answer would be 1/4 Kg
Hope this helps!
The temperatures would change and the water would become luke warm <span />
Answer:
a= (-g) from the moment the ball is thrown, until it stops in the air.
a = (0) when the ball stops in the air.
a = (g) since the ball starts to fall.
Explanation:
The acceleration is <em>(-g)</em> <em>from the moment the ball is thrown, until it stops in the air</em> because the movement goes in the opposite direction to the force of gravity. In the instant <em>when the ball stops in the air the acceleration is </em><em>(0)</em> because it temporarily stops moving. Then, <em>since the ball starts to fall, the acceleration is </em><em>(g)</em><em> </em>because the movement goes in the same direction of the force of gravity
Answer:
(a) W = 8.66 J
(b) Velocity = 2.40 m/s
Explanation:
(a) Work done is given as the product of force and displacement. That is:
W = F * d * cos(A)
Where F = force applied
d = distance moved
A = angle of ramp
Therefore, work done is:
W = 20 * 0.5 * cos30
W = 8.66 J
(b) Work done is equal to change in Kinetic energy. Since the initial kinetic energy is zero:
W = KE(final)
W = ½ * m * v²
Where v = final velocity
=> 8.66 = ½ * 3 * v²
v² = 5.773
v² = 2.40 m/s
