vf = 10 m/s. A ball with mass of 4kg and a impulse given of 28N.s with a intial velocity of 3m/s would have a final velocity of 10 m/s.
The key to solve this problem is using the equation I = F.Δt = m.Δv, Δv = vf - vi.
The impulse given to the ball with mass 4Kg is 28 N.s. If the ball were already moving at 3 m/s, to calculate its final velocity:
I = m(vf - vi) -------> I = m.vf - m.vi ------> vf = (I + m.vi)/m ------> vf = I/m + vi
Where I 28 N.s, m = 4 Kg, and vi = 3 m/s
vf = (28N.s/4kg) + 3m/s = 7m/s + 3m/s
vf = 10 m/s.
.
Answer:
52.49 Kg
Explanation:
Let m1 and v1 denote your mass and velocity respectively
Let m2 and v2 denote your friends mass and velocity respectively
Kinetic energy is given by
Since your kinetic energies are the same hence
and making m2 the subject then
Since v2 is v1+0.28v1=1.28v1
Substituting m1 for 86 Kg
The net force will point towards the acceleration of the object, as supported by Newton's second law.
No friction present means: Ek = Ep
So Ek = mgh = 10 * 9.8 * 2 = 196 J
The main advantage of an electromagnet over a permanent magnet is that the magnetic field can be quickly changed by controlling the amount of electric current in the winding. However, unlike a permanent magnet that needs no power, an electromagnet requires a continuous supply of current to maintain the magnetic field.
