Well, I never heard it expressed that way before,
but it might go something like this:
"Inertia is that property of all matter by which it
tends to maintain motion without any acceleration
until acted upon by an external force."
Newtons first law of motion.
The net force on the boy is zero.
Based on this analysis, I would expect the boy to <u>not accelerate</u>.
Answer:
X(t) = 9.8 *t - 4.9 * t^2
Explanation:
We set a frame of reference with origin at the hand of the girl the moment she releases the ball. We assume her hand will be in the same position when she catches it again. The positive X axis point upwards.The ball will be subject to a constant gravitational acceleration of -9.81 m/s^2.
We use the equation for position under constant acceleration:
X(t) = X0 + V0 * t + 1/2 * a *t^2
X0 = 0 because it is at the origin of the coordinate system.
We know that at t = 2, the position will be zero.
X(2) = 0 = V0 * 2 + 1/2 * -9.81 * 2^2
0 = 2 * V0 - 4.9 * 4
2 * V0 = 19.6
V0 = 9.8 m/s
Then the position of the ball as a function of time is:
X(t) = 9.8 *t - 4.9 * t^2
Answer:
Explanation:
Given:
- temperature of skin,
- initial temperature of steam vapour,
- latent heat of steam,
- mass of steam,
- specific heat of water,
- final temperature,
<em>Assuming that no heat is lost in the surrounding.</em>
<u>We know:</u>
<u>Now the total heat given by the steam to form water at the given conditions:</u>
..............................(1)
where:
latent heat given out by vapour to form water of 100°C
heat given by water of 100°C to come at 34°C.
putting respective values in eq. (1)
is the heat transferred to the skin.
