Answer:
option E
Explanation:
given,
diameter = 4 mm
shutter speed = 1/1000 s
diameter of aperture = ?
shutter speed = 1/250 s
exposure time to the shutter time

N is the diameter of the aperture and t is the time of exposure
now,


inserting all the values

N₂² = 4
N₂ = 2 mm
hence , the correct answer is option E
Answer:
π/10 rads
Explanation:
It takes an hour (60 minutes) for the minute's hand to turn a full circle or achieve an angular rotation of
2πl rad.
Now, number of periods of 3 minutes in an hour is;
Number of periods = 60/3 = 20 periods
Thus, 3 minutes rotation accounts for 1/20 of 2π the rotation of the minute's hand in an hour.
Thus;
Angular displacement = (1/20) * 2π = π/10 rads
Answer:
electric
<em>please give brainliest</em>
Answer:
The Force between the two charges is an attractive force of 16,000N
Explanation:
Expression for the electric force between the two charges is given by
F = (k*q1*q2) / r^2
Here, k = constant = 9 x 10^9 N*m^2 / C^2
q1 = - 2.0x10^-4C
q2 = + 8.0x10^-4C
r = 0.30 m
Substitute the given values in the above expression -
One charge is + and the other is a -, therefore the net force is an attractive force (opposites atract)
The attraction force is:
F= 9.0x10^9 * 2.0x10^-4 *8.0x10^-4 N/ 0.30^2
F= 16,000N
The answer is Near Earth Objects (NEOs).
Near Earth Objects (NEOs) have gained particular interest to scientists in their observations because of its potential threats to the Earth. It can be comets or asteroids. It is called Near Earth since their orbits are too close to cross the orbit of the Earth thus NEO can reach the space near-Earth that more likely give potential threats to the Earth.