Answer:
Frequency = 260 Hz and wavelength = 1.31 m
Explanation:
Given that,
A hammer begins vibrating back and forth at approximately 260 cycles per second.
(a) The frequency of an object is the number of vibrations per unit time. The frequency of the sound wave is 260 Hz.
(b) The speed of sound in air is 343 m/s. So,
Hence, this is the required solution.
Answer: 345600 J
Explanation: solution attached
KE= 1/2 mv²
Answer:
If the system consists of the block only, the work done by the gravity is negative.
If the system consists of the block and the earth the work done by the gravity is zero.
Explanation:
If the system consists of the block only, then the system experiences two external forces: one exerted by the hand that lifts the block vertically upward and other exerted by the earth (gravity), which is opposed to the movement of the system, so the work done by gravity is negative.
On the other hand, if the system consists of the block and the earth, then only exists a external force which is the exerted by the hand. So, the force exerted by gravity is zero.
A transformer is used to increase or decrease a voltage. BUT ... it has to be an AC voltage, or the transformer doesn't work.
