Water has a higher specific heat so it requires more energy to heat than sand.
I think the correct question would be, how do you measure sound. :)
you measure sound by using amplitude. It measures how forceful the sound is.
Thats how you know whether its loud or quite :)
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<span>work = 500*3 = 1500 J
1500J in 5 sec = 300 watts
Hope that helps:)</span>
The force required to start an object sliding across a uniform horizontal surface is larger than the force required to keep the object sliding at a constant velocity once it starts.
The magnitudes of the required forces are different in these situations because the force of kinetic friction is less than the force of static friction. <em>(d)</em>
