Answer:
Explanation:
height fallen = h , initial speed u = 0
time t = 2.4s
h = 1/2 x gt²
= .5 x 9.8 x 2.4²
= 28.22 m
Speed of striking the ground
v = gt
= 9.8 x 2.4
= 23.52 m/s
A ) When rock is thrown upwards
initial velocity u = - 19 m/s
g = 9.8 m/s²
h = ut + 1/2 gt²
50 = - 19t + .5 x 9.8 t²
4.9 t² - 19 t - 50 = 0
=5.7 s
B )
V = - -u+gt
= - 19 + 9.8 x 5.7
= 36.86 m/s
Answer:
Explanation:
The change in potential is then defined as the negative of the work done by that force. ... You can't have work done by gravity AND a change in gravitational potential energy. You have to do it one way or the other. This means that the most important step in solving work-energy problems is choosing a system.
the phenomenon is An object that has potential energy can transfer that energy into kinetic energy when the object begins to move, due to its mass or position. For example, a person jumping on a trampoline has potential energy when they reach the peak of a jump, and their force changes direction from upward to downward.
The component of waves must have same frequency and phase.
when the component of waves vibrate at the same rate and attain maximum point at the same time, reinforcement of the waves amplitude occur to cause a constructive interference.However, when the two waves are out of phase where one is at minimum when the other is at maximum a destructive interference happens.
here at the moment when bullet strikes the block it will have no external force on it
so here we can use momentum conservation
so we will have
so they move together with speed 1.98 m/s
Answer:Water pollution is a concern because since it is cycled threw the earths system it effect the earths system in a negative way.
Explanation:
I would wait for someone else to answer just in case I’m wrong.