Question

7. And 8. Please help, I would prefer someone to explain how to do it please

Answer 1

#7

Given that an electron revolves in a circle and the essential centripetal force is given as

$F = 4.60 \times 10^{-14}N$

now we need to find its speed

so we know that this force is given as

$F = \frac{mv^2}{R}$

$4.60 \times 10^{-14} = \frac{9.11 \times 10^{-31} v^2}{2 \times 10^{-2}}$

$v^2 = 1.01 \times 10^{15}$

$v = 3.18 \times 10^7 m/s$

#8

Here the force due to earth on satellite is the centripetal force to revolve around earth

so we can say that force due to earth is given as

$F = \frac{mv^2}{R}$

we know that

$m = 2.7 \times 10^3 kg$

$v = 4.7 \times 10^3 m/s$

$R = 1.8 \times 10^7 m$

now from above equation we have

$F = \frac{(2.7 \times 10^3)(4.7 \times 10^3)^2}{1.8 \times 10^7}$

$F = 3313.5 N$