Answer:
The answer cannot be determined.
Explanation:
The energy of the diver when he hits the pool will be equal to its potential energy , and for the temperature of the pool to rise up, this energy has to be converted into the heat energy of the pool.
The change in temperature then will be
Where m is the mass of water in the pool, c is the specific heat capacity of water, and is the added heat which in this case is the energy of the diver.
Since we do not know the mass of the water in the pool, we cannot make this calculation.
D because the tornado siren are supposed to be loud so everyone could hear
Answer:
I think it is D but don't count on it
Answer:
True
Explanation:
- A conservative force is a force whose work done does not depend on the path taken, but only on the final and starting point.
- The mechanical energy of an object is defined as the sum of the kinetic energy (K) and the potential energy (U): E = K + U
- The law of conservation of energy states that, in case only conservative forces are acting on the object, the mechanical energy of the object E is conserved
- In case non-conservative forces are acting on the object, the mechanical energy is no longer constant. An example of non-conservative force is the force of friction: when the force of friction is acting on a car in motion, the car is slowed down by the effect of the force, losing some of its kinetic energy, K. If the car is travelling on a flat road, then its potential energy U does not change: this means that the mechanical energy of the car, E, is decreasing, so it is no longer conserved.
- mechanical energy is conserved in all the listed situations
- true
- potential energy
- 490 J
- 750,000 J
EXPLANATION
1. sum of kinetic energy (KE) and potential energy (PE) is known as mechanical energy
- kinetic energy is the motion of an object
- potential energy is the position of an object
there is kinetic energy and other energies in the listed situation.
2. since the height decreases due to the fall, the potential energy also decreases but the speed increases and kinetic energy simultaneously increases so the potential energy is converted to kinetic energy.
3.the energy consumed by an object due to its position is known as potential energy
4. potential energy
PE = m g h
m = 10 kg mass of the object
g = 9.8 m/s^2 acceleration of gravity
h= 5 m height of the object from ground
substituting every value in the formula
PE = (10)(9.8)(5)
PE= 490 J
5. potential energy
PE = m g h
but given is the weight and the height of the elevator
W= 1500 N
h= 500 m
but weight of the object is equal to the product of acceleration of gravity and mass of the elevator
so, W = mg
so we can rewrite the formula as PE = Wh
PE = (1500)(500)
PE= 750,000 J