Answer:
44.64 seconds
Explanation:
t = Time taken
u = Initial velocity
v = Final velocity
s = Displacement
a = Acceleration due to gravity = 9.8 m/s²


<u>Time taken to reach 1180 m is 11.29 seconds</u>

<u>Time the rocket will keep going up after the engines shut off is 13.06 seconds.</u>

The distance the rocket will keep going up after the engines shut off is 836.05 m
Total distance traveled by the rocket in the upward direction is 1180+836.05 = 2016.05 m
The rocket will fall from this height

<u>Time taken by the rocket to fall from maximum height is 20.29 seconds</u>
Time the rocket will stay in the air is 11.29+13.06+20.29 = 44.64 seconds
Answer:
W = 290.7 dynes*cm
Explanation:
d = 1/5 cm = 0.2 cm
The force is in function of the depth x:
F(x) = 1000 * (1 + 2*x)^2
We can expand that as:
F(x) = 1000 * (1 + 4*x + 4x^2)
F(x) = 1000 + 4000*x + 4000*x^2
Work is defined as
W = F * d
Since we have non constant force we integrate

W = [1000*x + 2000*x^2 + 1333*X^3] evaluated between 0 and 0.2
W = 1000*0.2 + 2000*0.2^2 + 1333*0.2^3 - 1000*0 - 2000*0^2 - 1333*0^3
W = 200 + 80 + 10.7 = 290.7 dynes*cm
Answer:
-4.0 N
Explanation:
Since the force of friction is the only force acting on the box, according to Newton's second law its magnitude must be equal to the product between mass (m) and acceleration (a):
(1)
We can find the mass of the box from its weight: in fact, since the weight is W = 50.0 N, its mass will be

And we can fidn the acceleration by using the formula:

where
v = 0 is the final velocity
u = 1.75 m/s is the initial velocity
t = 2.25 s is the time the box needs to stop
Substituting, we find

(the acceleration is negative since it is opposite to the motion, so it is a deceleration)
Therefore, substituting into eq.(1) we find the force of friction:

Where the negative sign means the direction of the force is opposite to the motion of the box.
L = r x p = rmv = mr²ω
L = 0.25 x 0.75² x 12.5 = 1.758