How much work does it take to hold a 150 N weight above your head for 3 seconds?

To calculate the work done in holding a weight above your head, we need to know the distance the weight is lifted. Work can be calculated using the formula:

Work = Force x Distance x Cos(θ)

In this case, the force is 150 N, the distance is the height the weight is lifted, and θ is the angle between the force and the direction of motion (which is 0° if the weight is lifted straight up).

Since the weight is held above your head, we can assume it is lifted vertically, which means the angle θ is 0°, and the cosine of 0° is 1. Therefore, the equation simplifies to:

Work = Force x Distance

Now, to calculate the work done, we need the distance the weight is lifted. Let's assume it is lifted 2 meters. Then:

Work = 150 N x 2 m = 300 Joules

So, it would take 300 Joules of work to hold a 150 N weight above your head for 3 seconds, assuming the weight is lifted vertically over a distance of 2 meters.