Explanation:
A worker picks up the bag of gravel. We need to find the speed of the bucket after it has descended 2.30 m from rest. It is case of conservation of energy. So,
h = 2.3 m
So, the speed of the bucket after it has descended 2.30 m from rest is 6.71 m/s.
Explanation:
It is given that The Moon's center is 3.9x10⁸ m from Earth's center. The moon 1.5x10⁸ km from the Sun's center. We need to find the ratio of the gravitational forces exerted by Earth and the Sun on the Moon.
The gravitational force is given by :
It means
So,
r₁ = 3.9x10⁸ km
r₂= 1.5x10⁸ km
So,
Hence, the ratio of the gravitational forces exerted by Earth and the Sun on the Moon is 5:13.
Explanation:
It is given that,
Total mass is 70 kg
The truck exerts a constant force of 20 N.
Then the net force is given by :
F = ma
a is acceleration of rider
Initial velocity of rider is 0. So, using equation of kinematics to find the final velocity as :
Since, 1 m/s = 2.23 mph
4.28 m/s = 9.57 mph
So, the speed of the rider is 4.28 m/s or 9.57 mph.