a
a
b
b
a
b
a
This will really help you learn a lot.
Answer:
Explanation:
Work done in lifting the weight once = mgh
= 20 x 9.8 x (1.9+1.7)
= 705.6 J
= 705.6 / 4.2 calorie
= 168 cals
Total energy to be spent = 600 x 10³ cals
No of times weight is required to be lifted
= 600 x 10³ / 168
= 3.57 x 10³ times
Total time to be taken = 2 x 3.57 x 10³
= 7.14 x 10³ s
=119 minutes .
Constant speed because the time is directly proportional to the speed (2). The average speed is 2 m/s
A rotational force, also known as a torque, depends upon the force and where that force is applied; torque = lever arm x force. The lever arm is the perpendicular distance from the force to the axis of rotation.
