The work done will be equal to the potential energy of the piano at the final position
P.E=m.g.h
.consider the plank the hypotenuse of the right triangle formed with the ground
.let x be the angle with the ground=31.6°
.h be the side opposite to the angle x (h is the final height of the piano)
.let L be the length of the plank
sinx=opposite side / hypotenuse
= h/L
then h=L.sinx=3.49×sin31.6°=0.638m
weight w=m.g
m=w/g=3858/10=385.8kg
Consider Gravity g=10m/s2
then P.E.=m.g.h=385.8kg×10×0.638=2461.404J
then Work W=P.E.=2451.404J
Answer:
It is very rare to see a solar eclipse from your home, because the Earth, Sun, and the moon need to align just right. Not everyone in the world can view a solar eclipse, only some area can. A solar eclipse is where the moon blocks out the sun. If you think about it: Let's say you live in Florida, U.S.A. You may see the moon coming in front of the sun, but if you lived in California or sumthin', the moon and the sun wouldn't be aligned to form a solar eclipse. It all depends on location... so it is rare to see one.
Answer:
<em><u>It can be a solid, liquid, gas</u></em><em><u>,</u></em><em><u>plasma</u></em><em><u>,</u></em><em><u>etc</u></em><em><u>. When waves travel through a medium, the particles of the medium are not carried along with </u></em><em><u>the</u></em><em><u> </u></em><em><u>wave</u></em><em><u>.</u></em><em><u>For example, water waves have to travel in water. Sound waves need a solid, a liquid or a gas to travel in.</u></em>
consider the velocity of the ball towards the wall as negative and away from the wall as positive.
m = mass of the ball = 513 g = 0.513 kg
v₀ = initial velocity of the ball towards the wall before collision = - 14.7 m/s
v = final velocity of the ball away from the wall after collision = 11.3 m/s
t = time of contact with the wall = 0.038 sec
F = average force acting on the ball
using impulse-change in momentum equation , average force is given as
F = m (v - v₀)/t
inserting the values
F = (0.513) (11.3 - (- 14.7))/0.038
F = 351 N
Answer:
Explanation:
velocity of first projectile after 3 s
v = u - gt
v = 49.4 - 9.8 x 3
= 20 m /s
Velocity of second projectile after 3 s after being dropped from rest
v = u + gt
= 0 + 9.8 x 3
= 29.4 m /s
They will be moving in opposite direction at the time of meeting , so their relative velocity
= 20 + 29.4 = 49.4 m /s
From the frame of reference of the first projectile, the velocity of the second projectile will be 49.4 m /s .