Karma, and sensei. Maybe nagisa
Answer:
The rod`s charge must be positive, because the gravity force is pointing downwards and the electrostatic force must be pointing upwards (in order to balance the gravity force)
The charge is q_2 = 1.667 times 10^(-7) C
Explanation:
F_e = F_g
where F_g = m g and F_e= (1/4 pi e_0)*(q_1*q_2)/d^2,
please see the file attached for more details.
Answer:
0.74 s
Explanation:
We can solve the problem by using the following SUVAT equation:

where
d = 5.0 m is the displacement
u = 7.2 m/s is the initial velocity
a = -1.1 m/s^2 is the acceleration (which is negative since it is a deceleration)
t is the time
Substituting numbers into the equation, we find:

This is a second-order equation, whose solutions are given by:

And the solutions are
t = 0.74 s
t = 12.36 s
The solution we are looking for is the first one, because it corresponds to the first time at which the hockey puck has travelled the distance of 5.0 m, reaching the goal.
Answer:
2Hz
Explanation:
Find the diagram attached
Using the formula;
v = fλ
v is the velocity
f is the frequency
λ is the wavelength
Given the following
v = 3.2m/s
λ = 4.8/3 = 1.6m
Get the frequency
f = v/λ
f = 3.2/1.6
f = 2Hertz
Hence the frequency of the wave is 2Hz