A watt is a measure of power (the rate of energy change) equal to 1 j>s. (a) calculate the number of joules in a kilowatt- ho
1 answer:
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Answer:
22J
Explanation:
Given :
radius 'r'= 3cm
rotational inertia 'I'=4.5 x kgm²
mass on one side of rope ''= 2kg
mass on other side of rope'' =4kg
velocity'v' of mass ' = 2m/s
Angular velocity of the pulley is given by
ω = v /r => 2/ 3x
ω = 66.67 rad/s
For the rotating body, we have
KE = I ω²
= 10J
Next is to calculate kinetic energy of the blocks :
=12J
Therefore, the total kinetic energy will be
KE = =10 + 12
KE= 22J
Answer:
force becomes one - ninth
Explanation:
According to Coulomb's law in electrostatics, two charges can exert a force of attraction or repulsion on each other which is directly proportional to the product of two charges and inversely proportional to the square of distance between them.
Here both the charges remains same but the distance is variable.
So, we can say that
.... (1)
Where d be the distance between the tow charges
As the distance between two charges increases by factor of three, let the new force be F'.
.... (2)
Divide equation (2) by equation (1), we get
Thus, the force becomes one - ninth times the initial force.