Answer:
Explanation:
Let the charge on the ball bearing is q.
charge on glass bead, Q = 20 nC = 20 x 10^-9 C
Force between them, F = 0.018 N
Distance between them, d = 1 cm = 0.01 m
By use of Coulomb's law in electrostatics
By substituting the values
Thus, the charge on the ball bearing is
u=54 km/h
54*5/18=15 m/s
v=0m/s
t=?
acceleration=-0.5m/s^2
we know that a=v-u/t
so,
t=v-u/a
t=15-0/0.5
=15/0.5
=30
therefore, the time is 30 second
Hope this answer helps you..
time taken by the wave to reach the person is 0.2 s
As we know that the speed of the wave is given as
here we know that the wavelength of the wave is
now speed of the wave is given as
Now time taken by the wave to reach 5 m distance is
Answer:b