The velocity of the ball when it reaches the ground is equal to B. 68.6 m/s. This value was obtained from the formula Vf = Vi + at. Vf is the final velocity. Vi is the initial velocity. The acceleration is "a", while the time of travel is "t". The solution is:
<span>Vf = Vi + at
</span>Vf = 0 + (-9.8 m/s^2) (7 s)
Vf = -68.6 m/s
The negative sign denotes the direction of the ball.
Answer:
1793.7m
Explanation:
From the principle of conservation of energy; the kinetic energy substended by the object equals the potential energy sustain by the object when it gets to its maximum position.
Now the kinetic energy; is
K.E = 1/2 × m × v2
Where m is mass
v is velocity
Hence.
K.E = 1/2 × 2.25 × (187.5)^2
Now this should be same with the potential energy which is given as;
P.E = m× g× h
Where m is mass of object
g is acceleration of free fall due to gravity = 9.8m/S2
h is maximum height substain by the object.
Hence P.E = 2.25 × 9.8 × h
From the foregoing analysis of energy conversation it implies;
1/2 × 2.25 × (187.5)^2 =2.25 × 9.8 × h
=> 1/2 × (187.5)^2 = 9.8 × h
=>1/2 × (187.5)^2 / 9.8 = h
=> 1793.69m = h
h= 1793.69m
h =1793.7m to 1 decimal place
Answer:
The energy becomes 4 times greater.
Explanation:
We know that the energy of a wave is proportional to the square of its amplitude
E ∝ Amplitude^2
Since the original amplitude = 0.5 m
and the new amplitude becomes = 1 m
We are doubling the amplitude. This means that the new energy will be affected by a factor of 4
E_new ∝ (2*Amplitude)^2 =
E_new ∝ 4*(Amplitude)^2
E_new = 4*E
That would be only rotational motion
The correct answer is A. B. C. Hope this helps!!
