ball is dropped downwards. After 1 sec another ball is dropped from the same point . What is distance between them after 3sec A 25m B 20m C 50m D 9.8m
h1=1/2 g t^2
h2=1/2 g (t-1)^2
h1-h2=1/2 (9.8)(3^2-2^2)=about 5*5
To find the distance between the two balls after 3 seconds, we need to understand their individual displacements.
The distance traveled by a falling object is given by the equation:
d = ut + (1/2)gt²,
where:
- d is the distance traveled,
- u is the initial velocity (which is zero for objects dropped),
- t is the time, and
- g is the acceleration due to gravity, approximately 9.8 m/s².
Let's analyze the problem step-by-step:
1. First ball (dropped for 3 seconds):
Using the equation, the distance traveled by the first ball after 3 seconds is:
d₁ = 0 + (1/2)(9.8)(3)²
d₁ = 0 + (1/2)(9.8)(9)
d₁ = 0 + 44.1
d₁ = 44.1 m
2. Second ball (dropped for 2 seconds, as it was dropped after 1 second of the first ball):
Using the equation, the distance traveled by the second ball after 2 seconds is:
d₂ = 0 + (1/2)(9.8)(2)²
d₂ = 0 + (1/2)(9.8)(4)
d₂ = 0 + 19.6
d₂ = 19.6 m
3. The distance between them after 3 seconds is the difference between their distances traveled:
Distance between the two balls = d₁ - d₂
Distance = 44.1 - 19.6
Distance = 24.5 m
Therefore, the correct option is (A) 25m.