A sphere is charged with electrons to −9 × 10−6 C. The value given is the total charge of all the electrons present in the sphere. To calculate the number of electrons in the sphere, we divide the the total charge with the charge of one electron.
N = 9 × 10−6 C / 1.6 × 10−19 C
N = 5.6 x 10^13
Answer:
6.75m/s
Explanation:
using the second equation of motion, the time is calculated.
and with the formula a= (v - u)/t
where a is acceleration but in this case it's deceleration (and should be negated as you solve it ) .
v is final velocity
u is initial velocity
t is time taken
Answer:
λ = 6.602 x 10^(-7) m
Explanation:
In a double-slit interference experiment, the distance y of the maximum of order m from the center of the observed interference pattern on the screen is given as ;
y = mλD/d
Where;
D is the distance of the screen from the slits = 6.2 m
d is the distance between the two slits = 0.046 mm = 0.046 x 10^(-3) m
The fringes on the screen are 8.9 cm = 0.089 m apart from each other, this means that the first maximum (m=1) is located at y = 0.089 m from the center of the pattern.
Therefore, from the previous formula we can find the wavelength of the light:
y = mλD/d
So, λ = dy/mD
Thus,
λ = (0.046 x 10^(-3) x 0.089)/(1 x 6.2)
λ = 6.602 x 10^(-7) m
Answer:
-v/2
Explanation:
Given that:
- Collides with the wall going through a sliding motion on on the plane smooth surface.
- Upon rebounding from the wall its kinetic energy becomes one-fourth of the initial kinetic energy before collision.
<u>We know, kinetic energy is given as:</u>

consider this to be the initial kinetic energy of the body.
<u>Now after collision:</u>


Considering that the mass of the body remains constant before and after collision.

Therefore the velocity of the body after collision will become half of the initial velocity but its direction is also reversed which can be denoted by a negative sign.