Answer:
0.2695/s
Explanation:
Using the formula for calculating impulse
Impulse = m(v-u) = Ft
M is the mass
v is the final velocity.
u is the initial velocity
F is the force
t is the time
Get the time;
t = m(v-u)/F
t = 0.0055(220)/40
t = 0.0275s
Get the speed of the rifle
v = u+gt.
v = 0+9.8(0.0275).
v = 0.2695m/s
Hence the speed of the rifle is 0.2695m/s
Answer:
Final velocity of the car will be -9.28 m/sec
Explanation:
We have given that the car starts from the rest so initial velocity of the car u = 0 m /sec
Acceleration of the car
in negative direction so acceleration will be 
From first equation of motion we know that
v = u+at
So 
So final velocity will be -9.28 m/sec
The acceleration can be found by:

Where v= velocity and t= time
or
First, calculate the initial velocity of the dog given with the vertical height and the acceleration due to gravity which is calculated through the equation,
2ad = Vo²
Substituting the known values,
2(9.8 m/s²)(1.2 m) = V₀²
V₀ = 4.85 m/s
The kinetic energy is solved through the equation,
KE = 0.5mv²
Substituting the known values to the latest equation,
KE = 0.5 (7.2 kg)(4.85 m/s)²
KE = 17.46 J
Thus, the kinetic energy is 17.46 J.
Energy from the sun is referred to as solar energy.
So energy from the sun is solar energy.
hope it helps!!!