Find the final velocity of the particle if it is initially moving along the x axis with a velocity of −5 m/s.

Question

The force shown in the force-time diagram acts on a 4 kg object\

The total N is 6, N as in impulse

total time was 5 seconds

Answer 1

Hello Brian,

To solve this problem, we want to figure out how much impulse was imparted to the object by the force over the time given.

Impulse is given as:

Force*time = delta(p) <-- change in momentum

Momentum can then give us the change in velocity as follows:

delta(p) = mass*delta(v) <-- change in velocity

So, if the force of 6N is applied for 5 seconds in the positive x-direction (I'm assuming this because it's positive, but it might not be the case), we will have a change in momentum of 30 kg*m/s. Then, taking that number and dividing it by the 4 kg mass of the object, we get a change in velocity of 7.5 m/s. Again, if the force is applied rightward (positive x-direction), then the object will now be moving rightward at a speed of 2.5 m/s. If the force is applied leftward, the new speed will be -12.5 m/s because the force would be speeding it up in the negative x-direction.

Hope this helps. If you need help in the future, I'd be happy to assist. Cheers!

Justin