mandy drops a 2.0kg book from a height of 4.5m. how much work has gravity done on the book?
M=2.0kg
D= 4.5m
Not actually sure what to do next. Because none of the formulas work. I need work but I don't even know the force. To find force I need mass which I have but I don't have acceleration.
The acceleration is due to gravity
g = 9.8 m/s^2
The question is asking for work though. And the answer says it's 88J but I don't get how they got that as the answer
work is in Joules
2.0kg * 9.8 m/s^2 * 4.5m = 88.2 kg-m/s^2 = 88.2N-m = 88.2J
work = force * distance
force = mass * acceleration
Ohhh. That's what I missed. Okay thanks for explaining step by step. It helped a lot
To find the work done by gravity on the book, you need to calculate the gravitational potential energy.
The formula for gravitational potential energy is:
Potential Energy (PE) = mass (m) × acceleration due to gravity (g) × height (h)
In this case, the mass of the book (m) is given as 2.0 kg, the height (h) is 4.5 m, and the acceleration due to gravity (g) is approximately 9.8 m/s².
So, the work done by gravity can be found by multiplying the mass, acceleration due to gravity, and height:
Work = PE = m × g × h
Plugging in the values, we get:
Work = 2.0 kg × 9.8 m/s² × 4.5 m
Now you can calculate the work done by gravity.