Answer: 65000 seconds
Explanation:
Given that,
Current (I) = 2 mA
(Since 1 mA = 1 x 10^-3A
2 mA = 2 x 10^-3A)
Charge (Q) = 130 C
Time taken for a fully charged phone to die (T) = ?
Recall that the charge is the product of current and time taken.
i.e Q = I x T
130C = 2 x 10^-3A x T
T = 130C / (2 x 10^-3A)
T = 65000 seconds (time will be in seconds because seconds is the unit of time)
Thus, it will take a fully charged phone 65000 seconds to die
we have to use newtons law of gravitation which is
F=GMm/r^2
G=6.67 x 10^<span>-11N kg^2/m^2
</span>M=<span>(15kg)
</span>m=15 kg
r=(3.0m)^2<span>
</span>putting values we have
<span>=(6.67 x 10^-11N kg^2/m^2)(15kg)(15kg)/(3.0m)^2 </span>
=1.67 x 10^-9N
Well, since you only want direction, ignore the numbers. Use the right hand rule.
Current (pointer finger) points west (left).
Magnetic field (middle finger) points south (towards you).
Force (thumb) then points up (away from the earth)
