Answer:
Explanation:
We know that , If the frictional force on a system is zero , then the total energy of a system will be conserved.
By using energy conservation
KE₁ + U₁ = KE₂ + U₂
KE₁=Kinetic energy at location 1
U₁ =Potential energy at location 1
KE₂=Kinetic energy at location 2
U₂=Potential energy at location 2
Therefore, Raymond is thinking in a right way.
Answer:
It can be said to be reliable although it is not valid
Explanation:
This is because Reliability means an indicator of consistency, A measure should produce similar or the same results consistently if it measures the same quantity. So does the thermometer measures over 5days but it is not valid because it deviates from the real value