Answer:
35 km/hr
Explanation:
Average speed = (total of the speed)/(the sets of speeds given)
Direction does not matter in this instance since speed is only magnitude,
Average speed = (30 + 40)/2
Average speed = 70 ÷ 2
= 35 km/hr
Answer:
The value is 
Explanation:
From the question we are told that
The focal length of the objective is 
The focal length of the eyepiece is 
The tube length is 
Generally the magnitude of the overall magnification is mathematically represented as

Where
is the objective magnification which is mathematically represented as

=> 
=> 
is the eyepiece magnification which is mathematically evaluated as



So


Answer:
u=speed, w=wavelenght, f=frequency
It's known that u=w*f => f=u/w
u=20m/s ==> f=20/0,5 => f=40 Hz
w=0,50m
Explanation:
Answer:
A) 80 N
Explanation:
The closer the particles get, the stronger the Coulomb force, which elongates choices C and D. The Coulomb force is inversely proportional to the distance squared. If the distance is cut in half, the force is multiplied by the reciprocal of (1/2)^2, which is 4. Multiplying it out, 20 times 4 is 80 N.