Answer:
C. At the instant the ball reaches its highest point.
Explanation:
When a body is thrown up, it tends to come down due to the influence of gravitational force acting on the body. The body will be momentarily at rest at its maximum point before falling. At this maximum point, the velocity of the body is zero and since force acting on a body is product of the mass and its acceleration, the force acting on the body at that point will be "zero"
Remember, F = ma = m(v/t)
Since v = 0 at maximum height
F = m(0/t)
F = 0N
This shows that the force acting on the body is zero at the maximum height.
Answer:
a).11.546J
b).2.957kW
Explanation:
Using Inertia and tangential velocity
a).


Now using Inertia an w

average power=
b).
power=t*w
P=
P=2.957 kW
The correct answer for this question is this one: "measuring the temperature increase of water from doing work stirring it." This experiment is generally regarded as being first carried out by James Joule is this one, <span>measuring the temperature increase of water from doing work stirring it.</span>
Answer:
139.514 metres
Explanation:
Initial velocity of the truck = 6.6 m/s
Acceleration of the truck = 2.8 m/s^2
Time interval = 7.9 s
Therefore we use the formula,
s = ut + 1/2 at^2
*where s(the distance travelled)...u(the initial velocity)...t(the time period)
; s = 6.6(7.9) + 1/2 (2.8)(7.9)^2
; s = 52.14 + 87.374
The distance moved by the truck = 139.514m