Answer:
Explanation:
Electric field, E = 4.5 x 10^3 N/C
charge on electron, e = 1.6 x 10^-19 C
The relation between the force and the electric field is given by
F = q E
F = 1.6 x 10^-19 x 4.5 x 10^3
F = 7.2 x 10^-16 N
The magnitude of the force is
Given that,
Electric field intensity
Suppose, The electron when positioned at this location
We need to calculate the magnitude of the force
Using formula of electric field
Where, E = electric field
q = charge of electron
Put the value into the formula
Hence, The magnitude of the force is
Given
F = 55 N to ring the bell
P = 250 W
t = 0.85 s
Procedure
First let's calculate the force for 250W of power.
With 250W it is not possible to reach the bell to ring it.
Now let's calculate the value for 500W
Force is doubled when power is doubled
119 cm
Given heights : 200cm , 188 cm , 175 cm, 160 cm
since the eyes are at 95% level
95% of 200 cm = 190 cm
95% of 160 cm = 152 cm
hence the allowable height of mirror = 200 - ( 5 + 76 ) = 119 cm
and The mirror should be hung 75cm from the floor
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