Answer:
When the bag of apples are on the floor, the force of gravity is equal to the force applied in the upward direction.
But when the girl picks up the bag of apples, she applies a force on the bag of apples in the upward direction greater than that of the gravitational force.
Explanation:
Gravitational force for an object is always constant at a specific point. When an object is in the state of rest, there is an equal force opposite to the direction of Gravitational Force.
Now, to lift an object upwards, an external force must be applied that is greater than the force of gravitation.
So, when the girl picks up the bag of apples,
Gravitational Force < Force applied by the girl to lift the bag.
Answer:
A) s=1/2at^2
t=√(2s/a)=√(2x400)/10.0)=9.0s
B) v=at
v=10.0x9=90m/s
The correct answer is true
Answer:
Explained below
Explanation:
Newton's first law of motion: This law states that an object will remain at rest or continue in constant motion except it's acted upon by an external force. In projectile motion, the horizontal component of velocity will remain unchanged because we ignore air resistance since no force is acting in that horizontal direction.
Newton's second law of motion: This law states that force is the product of mass and acceleration. In projectile the force acts downwards, thus f = mg.
But g = a since internal forces will cancel out.
Thus, F = ma
Initially there were 10 bulbs of 60 Watt power
So total power of all bulbs = 60 * 10 = 600 W
now each bulb used for 4 hours daily
so total energy consumed daily
now we have total power consumed in 1 year
cost of electricity = 10 cents/ kWh
so total cost of energy for one year
Now if all 60 Watt bulbs are replaced by 30 Watt bulbs
So total power of all bulbs = 30 * 10 = 300 W
now each bulb used for 4 hours daily
so total energy consumed daily
now we have total power consumed in 1 year
cost of electricity = 10 cents/ kWh
so total cost of energy for one year
total money saved in 1 year
