Answer:
<u>6 bulbs</u> are needed to illuminate the room.
Explanation:
Given:
Measurement of kitchen (A) = 10 ft by 10 ft = 100 sq. ft
Number of footcandles (n) = 50
Lumens emitted by 1 bulb = 834
Number of bulbs (N) = ?
We are also given,
1 foot candle = 1 lumen/sq. ft
So, 50 foot candles = 50 lumens/sq. ft
Now, for an area of 1 sq. ft 50 lumens are emitted.
So, for an area of 100 sq. ft, lumens emitted = 50 × 100 = 5000 lumens
Now, one bulb emits = 834 lumes
Therefore, number of bulbs required for emitting 5000 lumens is given as:
So, 6 bulbs are needed to illuminate the room.
Answer:
1270 J
Explanation:
Recall that the mechanical energy of a system is the addition of the Potential energy and the Kinetic energy at any given time.
As the skier descends, potential energy is converted into kinetic energy, but the total mechanical energy should remain the same.
We see that it is not the case, so that difference is what has gone into thermal energy; 19500 J - 18230 J = 1270 J
Answer:
Explanation:
There are two types of collision.
(a) Elastic collision: When there is no loss of energy during the collision, then the collision is said to be elastic collision.
In case of elastic collision, the momentum is conserved, the kinetic energy is conserved and all the forces are conservative in nature.
The momentum of the system before collision = the momentum of system after collision
The kinetic energy of the system before collision = the kinetic energy after the collision
(b) Inelastic collision: When there is some loss of energy during the collision, then the collision is said to be inelastic collision.
In case of inelastic collision, the momentum is conserved, the kinetic energy is not conserved, the total mechanical energy is conserved and all the forces or some of the forces are non conservative in nature.
The momentum of the system before collision = the momentum of system after collision
The total mechanical energy of the system before collision = total mechanical of the system after the collision
Answer:
Average Velocity = 3.65 m/s
Explanation:
Average Velocity 
