Answer:
Mass, m = 125 kg
Explanation:
Let us assume that the question says, "What is the mass of an object whose velocity is 400 m/s and the kinetic energy of 10⁷ J.
The kinetic energy of an object is :
So, the mass of the object is 125 kg.
Consider a long train moving at speed v. Now consider a passenger throwing a ball inside this train, towards the back of the train, with same velocity v (but in the opposite direction of the train movement).
- A passenger inside the train will see the ball moving with speed v
- For an observer outside the train, however, the ball will appear as still. In fact, for him the ball will have a speed v (given by the movement of the train) -v (velocity of the ball but moving in the opposite direction), so the net velocity will be v+(-v)=0.
Answer:
Time taken to reach final velocity = 5.5 second
Explanation:
Given:
Initial velocity (Starting from rest)(u) = 0 m/s
Acceleration of ball (a) = 1 m/s²
Final velocity (v) = 5.5 m/s
Find:
Time taken to reach final velocity
Computation:
Using first equation of motion;
v = u + at
where,
v = final velocity
u = initial velocity
a = acceleration
t = time taken
5.5 = 0 + (1)(t)
5.5 = t
Time taken to reach final velocity = 5.5 second
Answer:
v = K √(E / ρ)
Explanation:
Modulus of elasticity has units of N/m², or kg/m/s².
Density has units of kg/m³.
Velocity has units of m/s.
If we divide modulus of elasticity by density, we can eliminate kg:
E / ρ = [kg/m/s²] / [kg/m³]
E / ρ = [m²/s²]
Taking the square root gets us units of velocity:
√(E / ρ) = [m/s]
Multiply by the constant K:
v = K √(E / ρ)
