The engines of a 1.20 x 10^5 N rocket exert an upward thrust of 2.00 x 10^5 N for 1.50 minutes upon lift off.

What is the impulse exerted on the rocket?

What is the velocity of the rocket at the end of the 1.50 minute period?

impulsr=force*time=2E5*90 N-seconds

changevelocity=impulse/massrocket

I don't understand where the 90 comes from

To find the impulse exerted on the rocket, you can use the formula:

Impulse = Force x Time

In this case, the force exerted by the rocket engines is 2.00 x 10^5 N, and the time for which the force is applied is 1.50 minutes. However, we need to convert the time to seconds in order to use the formula correctly.

1 minute is equal to 60 seconds, so 1.50 minutes is equal to 1.50 x 60 = 90 seconds.

Now, you can substitute the values into the formula:

Impulse = (2.00 x 10^5 N) x (90 s)

Calculate the product to find the impulse exerted on the rocket.

Next, let's calculate the velocity of the rocket at the end of the 1.50 minute period. You can use the concept of impulse-momentum to find the final velocity of an object.

The impulse-momentum equation is:

Impulse = Change in Momentum

Since the rocket is initially at rest, the initial momentum is zero. Therefore, the impulse exerted on the rocket is equal to the change in momentum.

The formula for momentum is:

Momentum = Mass x Velocity

We know the impulse exerted on the rocket from the previous calculation, and we can assume the rocket's mass is constant. Therefore, we can rearrange the equation to solve for the velocity:

Impulse = Mass x Change in Velocity

Rearrange the formula to solve for the change in velocity:

Change in Velocity = Impulse / Mass

Substitute the values of impulse and mass into the formula. The mass of the rocket is not given in the question, so we cannot determine the actual value of the velocity.

However, you can divide the impulse (calculated in the previous step) by the mass (assuming a value for the rocket's mass) to find the change in velocity.