Please i really need help! :/

2 answers:

8 0

Answer: D

Explanation:
Let us examine the given actions to see which ones generate heat and sound energy from mechanical energy.

A) Stretching a string.
The mechanical stretching creates tension in the string, which is released when the tension is removed. The generation of thermal or sound energy is minimal or negligible.

B) Squeezing a sponge ball
The sponge ball experiences compressive loading. This generates minimal or no heat and sound energy.

C) Throwing a ball upwards in the air
Air friction generates minimal or no heat at low velocities. At low velocities the pressure waves are too small to generate sound.

D) Striking a hammer on a nail.
A tremendous amount of force is applied over a small area to generate very high stresses that are in the plastic zone. A high amount of thermal energy is generated and the localized disturbance of the air generates audible sound.
This is the correct situation.

Andru [333]3 years ago

8 0

Answer:

the answer is D, I took the test

Explanation:

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