Answer:
The rock's speed after 5 seconds is 98 m/s.
Explanation:
A rock is dropped off a cliff.
It had an initial velocity of 0 m/s. And now it is moving downwards under the influence of gravitational force with the gravitational acceleration of 9.8 m/s².
Speed after 5 seconds = V
We know that acceleration = average speed/time
In our case,
g = ((0+V)/2)/5
9.8*5 = V/2
=> V = 2*9.8*5
V = 98 m/s
Answer:
The image distance is 17.56 cm
Explanation:
We have,
Height of light bulb is 3 cm.
The light bulb is placed at a distance of 50 cm. It means object distance is, u =-50 cm
Focal length of the lens, f = +13 cm
Let v is distance between image and the lens. Using lens formula :

So, the image distance is 17.56 cm.
"<em>F = dP/dt. </em> The net force acting on an object is equal to the rate at which its momentum changes."
These days, we break up "the rate at which momentum changes" into its units, and then re-combine them in a slightly different way. So the way WE express and use the 2nd law of motion is
"<em>F = m·A.</em> The net force on an object is equal to the product of the object's mass and its acceleration."
The two statements say exactly the same thing. You can take either one and work out the other one from it, just by working with the units.
Answer: Electromagnetic radiation
Explanation:
Electromagnetic radiation is a combination of oscillating electric and magnetic fields, which propagate through space carrying energy from one place to another.
To understand it better:
This radiation is spread thanks to the electromagnetic fields produced by moving electric charges and their sources can be natural or man-made.
It should be noted that the energy of electromagnetic radiation can vary and depending on its frequency it can be useful for various situations.