Answer:
The distance the ball moves up the incline before reversing its direction is 3.2653 m.
The total time required for the ball to return to the child’s hand is 3.2654 s.
Explanation:
When the girl is moving up:
The final velocity (v) = 0 m/s
Initial velocity (u) = 4 m/s
a = -0.25g = -0.25*9.8 = -2.45 m/s². (Negative because it is in opposite of the velocity and also it deaccelerates while going up).
Let time be t to reach the top.
Using
v = u + a×t
0 = 4 - 2.45*t
t = 1.6327 s
Since, this is the same time the ball will come back. So,
<u>Total time to go and come back = 2* 1.6327 = 3.2654 s
</u>
To find the distance, using:
v² = u² + 2×a×s
0² = 4² + 2×(-2.45)×s
s = 3.2653 m
<u>Thus, the distance the ball moves up the incline before reversing its direction is 3.2653 m.</u>
Answer:
The correct option is C
Explanation:
The pendulum bob would return at the same time because the initial angle a pendulum bob is dropped does not affect it's period (the time it takes for the pendulum to move back and forth), however the one with a larger angle move faster but would eventually arrive at the same "starting point" due to varying displacements made.
Answer:
L = mp*v₀*(ms*D) / (ms + mp)
Explanation:
Given info
ms = mass of the hockey stick
uis = 0 (initial speed of the hockey stick before the collision)
xis = D (initial position of center of mass of the hockey stick before the collision)
mp = mass of the puck
uip = v₀ (initial speed of the puck before the collision)
xip = 0 (initial position of center of mass of the puck before the collision)
If we apply
Ycm = (ms*xis + mp*xip) / (ms + mp)
⇒ Ycm = (ms*D + mp*0) / (ms + mp)
⇒ Ycm = (ms*D) / (ms + mp)
Now, we can apply the equation
L = m*v*R
where m = mp
v = v₀
R = Ycm
then we have
L = mp*v₀*(ms*D) / (ms + mp)
The exact same amount of force will be exerted but in opposite direction
