The statement is false. Balanced forces can NOT change the speed OR direction of an object's motion. (See Newton's #1 law of motion.)
This is a great problem if you like getting tied up in knots
and making smoke come out of your brain.
I found that it makes the problem a lot easier if I give the objects some
numbers. I'm going to say that the mass of Object 5 is 20 clods.
Let the mass of Mass of Object 5 be 20 clods .
Then . . .
-- The mass of Object 2 is double the mass of Object 5 = 40 clods.
-- The mass of Object 4 is half of the mass of Object 5 = 10 clods.
and
-- the mass of Object 3 is half of the mass of Object 4 = 5 clods.
So now, here are the masses:
Object #1 . . . . . unknown
Object #2 . . . . . 40 clods
Object #3 . . . . . 5 clods
Object #4 . . . . . 10 clods
Object #5 . . . . . 20 clods .
Now let's check out the statements, and see how they stack up:
Choice-A:
Object 3 and Object 5 exert the same gravitational force on Object 1.
Can't be.
Objects #3 and #5 have different masses, so they can't both
exert the same force on the same mass.
Choice-B.
Object 2 and Object 4 exert the same gravitational force on Object 1.
Can't be.
Objects #2 and #4 have different masses, so they can't both
exert the same force on the same mass.
Choice-C.
The gravitational force between Object 1 and Object 2 is greater than
the gravitational force between Object 1 and Object 4.
Yes ! Yay !
Object-2 has more mass than Object-4 has, so it must exert more force on
ANYTHING than Object-4 does, (as long as the distances are the same).
Choice-D.
The gravitational force between Object 1 and Object 3 is greater than the gravitational force between Object 1 and Object 5.
Can't be.
Object-3 has less mass than Object-5 has, so it must exert less force on
ANYTHING than Object-4 does, (as long as the distances are the same).
Conclusion:
If the DISTANCE is the same for all the tests, then Choice-C is
the only one that can be true.
Answer:
(a) 
(b) 
(c) 
Explanation:
Given that,
(a) An electron accelerated from rest through a potential difference of 100 V. The De Broglie wavelength in terms of potential difference is given by :
Where
m and e are the mass of and charge on an electron
On solving,
V = 100 V
(b) V = 1 kV = 1000 V
(c) If 
Hence, this is the required solution.
Density is a property of the substance, and doesn't depend on
how much of it you have.
One drop of the shampoo and a supertanker-full of the same
shampoo have the same density.
