Answer : The momentum of ball is, 15 kg.m/s
Explanation :
Momentum : It is defined as the motion of a moving body. Or it is defined as the product of mass of velocity of an object.
Formula of momentum is:
where,
p = momentum = ?
m = mass = 1.5 kg
v = velocity = 10 m/s
Now put all the given values in the above formula, we get:
Therefore, the momentum of ball is 15 kg.m/s
Answer:
Explanation:
a ) Direction of the magnetic field will be in positive x direction.
The direction of the vector E X B gives the direction of motion of wave.
b ) Magnitude of magnetic field is given by the relation
E₀ / B₀ = c , c is velocity of light
B₀ = E₀ / c
= 20 / (3 x 10⁸)
= 6.67 x 10⁻⁸ T
c ) Average power flowing per unit area by this wave is called Poynting vector
c ε₀E₀² , ε₀ = 8.85X10⁻¹²
= 3 X 10⁸ X 8.85 X 10⁻¹² X 20²
= 1.062 W m⁻²
Answer:
The force acting on a body is always equal to the product of the mass of the body and its acceleration.
Explanation:
The force of a body is defined as the product of mass and acceleration of the body.
According to Newton's second law, wherever there is a change in momentum of the body for an interval of time, there is a force acting on it.
F = (mv - mu) / t
= m (v -u) /t
= m a
Where,
(v - u)/t - is the change in velocity of the body in the interval of time. It is equal to the acceleration of the body.
Hence, the equation for the force for any body becomes, F = m x a
The correct answer is B. Fuse.
Fuses were commonly used in houses up to recent ages, when circuit breakers became the more popular options, as they don't have to be changed every time they melt, since they don't melt.
Answer:
t = 0.28 seconds
Explanation:
Given that,
Force acting on a firework, F = 700 N
The momentum of the firework, p =200 kg-m/s
We need to find the time before it explodes. Ket the time be t. We know that, the rate of change of momentum is equal to external frce. So,

So, the required time is equal to 0.28 seconds.