Answer:
Explanation:
Capacitor of 0.75μF, charged to 70V and connect in series with 55Ω and 140 Ω to discharge.
Energy dissipates in 55Ω resistor is given by V²/R
Since the 55ohms and 140ohms l discharge the capacitor fully, the voltage will be zero volts and this voltage will be shared by the resistor in ratio.
So for 55ohms, using voltage divider rule
V=R1/(R1+R2) ×Vt
V=55/(55+140) ×70
V=19.74Volts is across the 55ohms resistor.
Then, energy loss will be
E=V²/R
E=19.74²/55
E=7.09J
7.09J of heat is dissipated by the 55ohms resistor
Hi Pupil Here is your answer ::
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1 The shape of the Body
Example : The shape of the ball lying on a floor can be changed by pressing it.
2 Direction of the Body
Example : The direction of motion of moving ball can be changed by hitting it with a bat.
3 The speed of the Body
Example : A ball at rest can be set in motion if force is applied only
4. Size of the Body
Example : The length of a spring tied and on one end can be increased by pulling it.
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Hope this helps .......
The correct answer is<span> B.The speed of sound in air is directly proportional to the temperature of the air.
When the temperature increases so does the speed of sound. Sound is faster by </span>0.60 m/s for every higher degree in air temperature because the air density is reduced and the sound can travel faster.
The main reason why bells are made up of metals instead of wood is because metal is much more dense than wood, meaning that it resonates at much stronger frequencies. Wood has far too much air in it to make loud noises when struck.
D. The molecules in water are constantly moving.
They are able to do this because they move around to take whatever shape of the container.