A 4 kg object is lifted 1.5m.
a)how much work is against gravity?
B)Repeat if the object is lowered instead of lifted?
work = mgh
To calculate the work done against gravity, you need to use the formula:
Work = force x distance
The force in this case is the weight of the object, which is given by:
Weight = mass x gravity
Where the mass is 4 kg, and gravity is approximately 9.8 m/s². Now, let's calculate:
a) Work done against gravity when the object is lifted:
First, calculate the weight of the object:
Weight = 4 kg x 9.8 m/s² = 39.2 N
Now, you can calculate the work done:
Work = force x distance = 39.2 N x 1.5 m = 58.8 Joules
So, the work done against gravity when the object is lifted is 58.8 Joules.
b) If the object is being lowered instead of lifted, the work done against gravity is the same in magnitude but opposite in sign. In this case, the distance is still 1.5 m, but the direction is opposite. So, the work done against gravity when the object is lowered will be -58.8 Joules.
It is important to note that the negative sign indicates that work is being done by gravity instead of against gravity when the object is lowered.