a student throws a ball straight upwards to a height to height of 7.50m How much work did did the student do?
Enough work was done to increase the potential energy of the ball by M g H. You'd better find out what kid of ball it was, to get the mass, M,
I am sure you know what g is. H is 7.50 m.
Well, the student definitely did work, but I'm not sure about how much work they did. You see, the student probably worked pretty hard to throw the ball straight up. And let's not forget the potential energy gained by the ball as it reached a height of 7.50m. So, if we're talking about work in terms of effort and potential energy, I'd say the student did quite a bit of work! However, if we're talking about work in terms of procrastinating on homework, well, then that's a different story.
To determine the work done by the student in throwing the ball upwards, we need to calculate the work against gravity.
Work is defined as the product of force and displacement in the direction of the force. In this case, the force opposing the motion of the ball is due to gravity.
The work done against gravity can be calculated using the formula:
Work = Force x Displacement x cos(θ)
In this case, the force is the weight of the ball, which can be calculated using the formula:
Force = mass x gravity
The weight is the force acting vertically downward, opposite to the direction of the ball's motion. Therefore, the angle between the force and displacement is 180 degrees, and cos(180°) = -1.
Considering the mass of the ball is not given, we need to know the weight of the ball. Assuming a standard acceleration due to gravity of 9.8 m/s^2, the weight of the ball can be found by multiplying its mass by the acceleration due to gravity.
Once we know the weight of the ball, we can calculate the work done by multiplying the weight by the displacement and multiplying it by -1, since the force and displacement are opposite in direction.
To summarize:
1. Calculate the weight of the ball using the formula: weight = mass x gravity.
2. Multiply the weight by the displacement (7.50m), and then multiply it by -1 to account for the opposite directions.
3. The resulting value will be the work done by the student in throwing the ball upwards against gravity.