Answer:Same magnitude
Explanation:
When ball is dropped from shoulder height h then velocity at the bottom is given by
if it makes elastic collision then it will acquire the same velocity and riser up to the same height
If m is the mass of ball then impulse imparted is given by
Thus impulse imparted by gravity and Floor will have same magnitude of impulse but direction will be opposite to each other.
Seven days after a waxing gibbous moon, the moon will be waning gibbous, and at some point during that seven days, it will have been Full.
Answer:C The final velocity is half of trained car B's initial velocity.
Explanation:
Answer:
in CGS system G is denoted as gram
Answer:
Its resistance decreases
Explanation:
The resistance of a wire is directly proportional to the length of the wire and inversely proportional to the cross sectional area of the wire.
Mathematically,
R1 =¶L1/A1... (1)
R1= ¶L1/{Πd²/4}
R1= 4¶L1/Πd²
where;
¶ is the constant of proportionality which is the resistivity of the material
L is the length of the wire
A is the cross sectional area
A1 = Πd²/4
If the length is quadrupled and its diameter tripled
The new length L2 will be 4L1
New area A2 = Π(3d)²/4 = 9Πd²/4
The resistance will become
R2 = ¶(4L1)/{9Πd²/4}
R2 = 4¶L1×4/9Πd²
R2 = 16¶L1/9Πd²... (2)
R2/R1 = 16¶L1/9Πd²÷4¶L1/Πd²
R2/R1 = 16¶L1/9Πd²×Πd²/4¶L1
R2/R1 = 16/9×1/4
R2/R1 = 16/36
R2/R1 = 4/9
R2 = 4/9R1
This shows that the resistance of the wire decreases
