Answer:
KE = 0.162 KJ
Explanation:
given,
mass of bullet (m)= 20 g = 0.02 Kg
speed of the bullet (u)= 1000 m/s
mass of block(M) = 1 Kg
velocity of bullet after collision (v)= 100 m/s
kinetic energy = ?
using conservation of momentum
m u = m v + M V
0.02 x 1000 = 0.02 x 100 + 1 x V
20 = 2 + V
V = 18 m/s
now,
Kinetic energy of the block
KE = 162 J
KE = 0.162 KJ
<span>Every 10s 5 waves; t1 = 2s for each wave
When v = 1.5m/s, 3 waves in 10s t2 = 10 / 3s
Calculating the frequency in first case f1 = 5 / 10 = 0.5
Calculating the frequency in second case f2 = 3 / 10 = 0.3
Using the Doppler formula f = (1-v/c) f0
For the formula f = f2, v = velocity of boat= 1.5 m/s, f0 = f1, c is velocity of wave
0.3 = 0.5 x (1 - 1.5/c) => 1.5/c = 1 - 0.6 => 1.5/c = 0.4 => c = 1.5/0.4
Velocity of the wave = 3.75 m/s</span>
The law states that external forces cause objects to accelerate, and the amount of acceleration is directly proportional to the net force and inversely proportional to the mass of the object.
If you can’t copy and paste it just reword it
