The easiest way to explain it is roughly identical to the way that your teacher explained it in class. If there were any easier way ... like writing it here in a few paragraphs ... then that's what the teacher would have done. You would have been given the easy explanation on the first day of class, printed on one sheet of paper, and you would have had the rest of the year to practice it and get really good at it.
If the class spent a month teaching it, then that's about how long it takes. Sorry.
As long as it sits on the shelf, its potential energy
relative to the floor is . . .
Potential energy = (mass) x (gravity) x (height) =
(3 kg) x (9.8 m/s²) x (0.8m) = <u>23.52 joules</u> .
If it falls from the shelf and lands on the floor, then it has exactly that
same amount of energy when it hits the floor, only now the 23.52 joules
has changed to kinetic energy.
Kinetic energy = (1/2) x (mass) x (speed)²
23.52 joules = (1/2) x (3 kg) x (speed)²
Divide each side by 1.5 kg : 23.52 m²/s² = speed²
Take the square root of each side: speed = √(23.52 m²/s²) = <em>4.85 m/s </em> (rounded)
Earth-like planet in another solar system
Hope this helps!!
Answer
given,
focal length of lens A = 5.77 cm
focal length of lens B= 27.9 cm
flies distance from mirror = 11.3 m
now,
Using lens formula
q =11.79 cm
image of lens A is object of lens B
distance of lens = 59.9 - 11.79 = 48.11
now, Again applying lens formula
q' =66.41 cm
hence, the image distance from the second lens is equal to q' =66.41 cm
Answer: a) 8.2 * 10^-8 N or 82 nN and b) is repulsive
Explanation: To solve this problem we have to use the Coulomb force for two point charged, it is given by:
Replacing the dat we obtain F=82 nN.
The force is repulsive because the points charged have the same sign.
