Question 97: Motion in 1D

Question

From a building two balls A and B  are thrown such that A is thrown upwards and B downwards ( both vertically with the same speed ). If vA and vB are their respective velocities on reaching the ground, then

Accepted Answer

Assume the initial velocity of each particle is = u
And height of building = h
If final velocity of A is v
A
then v
A
2
= u
2
+ 2(-g)(-h) = u
2
+ 2gh
If final velocity of B is v
B
then v
B
2
= u
2
+ 2gh
$$	herefore$$ v
A
= v
B
Sign Rule :
Take the direction of initial velocity positive opposite direction as negative.
Here for ball A initial velocity u is upward so upward is positive and downward is negative. That is why gravity is  = - g and height = - h
And for ball B initial velocity u is downward so downward is positive and upward is negative. That is why gravity is  = + g and height = + h

Answer

$${v_B} > {v_A}$$

Answer

$${v_A} = {v_B}$$

Answer

$${v_A} > {v_B}$$

Answer

their velocities depend on their masses.

Motion in 1D

From a building two balls A and B are thrown such that A is thrown upwards and B downwards ( both vertically with the same speed ). If vA and vB are their respective velocities on reaching the ground, then

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