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A rope pulls a 2.0 kg bucket straight up, accelerating it from rest at 2.2 m/s2 for 3.0 s.

(a) calculate the displacement of the bucket.
(b) calculate the work done by each force acting on the bucket.
(c) calculate the total mechanical work done on the bucket.
(d) calculate the net force acting on the bucket and the work done by the net force. compare your answer to the total mechanical work done on the bucket as calculated in (c).

User TavoGLC
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Final answer:

The displacement of the bucket can be calculated using the equation s = ut + 0.5at^2. The work done by each force can be calculated using the equation W = F x d x cos(theta). The net force acting on the bucket can be calculated using Newton's second law.

Step-by-step explanation:

(a) To calculate the displacement of the bucket, we can use the equation:

s = ut + 0.5at^2

where s is the displacement, u is the initial velocity, t is the time, and a is the acceleration.

Given that the bucket starts from rest, the initial velocity (u) is 0 m/s.

Plugging in the values, we get:

s = 0(3.0) + 0.5(2.2)(3.0)^2 = 9.9 m

Therefore, the displacement of the bucket is 9.9 meters.

(b) To calculate the work done by each force, we can use the equation:

W = F x d x cos(theta)

where W is the work done, F is the force, d is the displacement, and theta is the angle between the force and displacement.

- The work done by the rope pulling force is:

W_rope = F_rope x d x cos(0) = F_rope x d

- The work done by the gravitational force is:

W_gravity = F_gravity x d x cos(180) = -F_gravity x d

- The work done by friction is:

W_friction = F_friction x d x cos(180) = -F_friction x d

(c) The total mechanical work done on the bucket is the sum of the work done by each force:

Total work = W_rope + W_gravity + W_friction

(d) The net force acting on the bucket can be calculated using Newton's second law:

F_net = m x a

where F_net is the net force, m is the mass, and a is the acceleration.

Plugging in the values, we get:

F_net = 2.0 kg x 2.2 m/s^2 = 4.4 N

The work done by the net force can be calculated using the equation:

W_net = F_net x d x cos(theta)

Since the acceleration is in the same direction as the displacement, the angle between the force and displacement is 0 degrees.

Therefore, the work done by the net force is:

W_net = F_net x d


We can compare this value to the total mechanical work done on the bucket calculated in (c) to see if they are equal.

User Wickedchicken
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