Answer:
v = 42.92 m/s
Explanation:
Given,
initial speed of the ball, v = 11 m/s
time taken to hit the ground = 5.5 m/s
velocity of the ball just before it hit the ground, v = ?
time taken by the ball to reach the maximum height
using equation of motion
v = u + at
final velocity = 0 m/s
0 = 11 - 9.8 t
t = 1.12 s.
time taken by the ball to reach the water from the maximum height
t' - 5.5 -1.12 = 4.38 s
using equation of motion for the calculation of speed just before it hit the water.
v = u + a t
v = 0 + 9.8 x 4.38
v = 42.92 m/s
Velocity of the ball just before it reaches the water is equal to v = 42.92 m/s
To look for the acceleration, it will come from:
vf^2=v0^2+2ad
where:
vf = final velocity = 0
v0 = initial velocity =251 m/s
a = acceleration
d= distance traveled = 0.237 m
0=251^2+2a(0.237 )
a= -251 ^2 / (2*0.237) =-132 913.502 m/s/s
we find the force from:
F = ma = 0.0115kg*(-1.32x10^5m/s/s) = -1518 N
the negative sign shows that the force is in the direction contradictory the
bullet's motion
Answer:
option(d)
Explanation:
The frequency of a wave is the property of the source of wave.
The velocity of all the electromagnetic waves is same as the speed of light. It only changes as the light passes through one medium to another.
The frequency is defined as the number of waves coming out from the source in 1 second.
As the frequency of wave increases, the number of wave coming per second increases.
So, the number of waves passing by increases but the speed remains same.
Option (d)
The whiter the color the more young it is and the more energy it emits