Question 1: Define the term 'work done' in physics.

Answer: Work done is the product of the force applied to an object and the displacement in the direction of the force, measured in joules (J).

Question 2: Explain the conditions under which work is considered to be done in a physical context.

Answer: Work is done when a force causes an object to move in the direction of the applied force, resulting in displacement.

Question 1: A person applies a force of 50 N to move a box 4 meters across the floor. Calculate the work done.

Answer: Work done = Force x Displacement = 50 N x 4 m = 200 Joules

Question 2: A conveyor belt does 1500 Joules of work in moving packages over a distance of 300 meters. What is the average force exerted by the belt?

Answer: Force = Work / Distance = 1500 J / 300 m = 5 Newtons

Question 1: Describe a simple experiment to demonstrate the concept of work done involving a pulley, a weight, and a frictionless surface. Include the variables involved and safety precautions.

Answer: An experiment can involve attaching a weight to a pulley with a string passing over a frictionless surface or low-friction wheel. When the weight is released, it pulls the string, causing a small object to move. Variables include the force applied (weight), displacement, and friction. Safety precautions include ensuring the setup is stable, not exceeding the weight limit of the pulley, and keeping hands clear of moving parts during operation.

Question 1: A worker lifts a box weighing 200 N to a height of 2 meters. How much work has the worker done? Explain your reasoning.

Answer: Work done = Force x Displacement = 200 N x 2 m = 400 Joules. The worker has done 400 Joules of work in lifting the box because the force exerted (weight) and the vertical displacement are in the same direction.

Question 2: In a manufacturing process, a machine performs 5000 Joules of work to move objects over a distance of 50 meters. If the force exerted by the machine remains constant, what is the magnitude of that force?

Answer: Force = Work / Distance = 5000 J / 50 m = 100 Newtons

Question 1: Explain how understanding work done is important in designing energy-efficient vehicles.

Answer: Understanding work done helps engineers design vehicles that minimize energy loss during motion, improving fuel efficiency by optimizing the force and distance factors involved in acceleration and braking.

Question 2: Describe how work done relates to the energy transfer in lifting objects in construction work.

Answer: When lifting objects, work done transfers chemical or electrical energy into potential energy stored in the lifted object. The amount of work done depends on the weight and height lifted, illustrating the conversion of energy forms and emphasizing the importance of applying the correct force to prevent unnecessary energy expenditure.