| ⇦ | 
| ⇨ |
A ball is dropped from a high rise platform at t = 0 starting from rest. After 6 seconds another ball is thrown downwards from the same platform with a speed v.The two balls meet at t = 18s. What is the value of v?(take g = 10 m/s²)
Options
(a) 75 m/s
(b) 55 m/s
(c) 40 m/s
(d) 60 m/s
Correct Answer:
75 m/s
Explanation:
Clearly distance moved by 1st ball in 18 s = distance moved by 2nd ball in 12 s. Now, distance moved in 18 s by 1st ball 1/2 x 10 x 18²
= 90 x 18 = 1620 m. Distance moved in 12 s by 2nd ball = ut + 1/2 gt²
1620 = 12v + 5 x 144
v = 135 – 60 = 75 ms
Related Questions: - In the half wave rectifier circuit operating from 50 Hz mains frequency,
- The drive shaft of an automobile rotates at 3600 rpm and transmits 80 HP
- A body oscillates with amplitude of 10 cm in a horizontal platform.
- A gas of monoatomic hydrogen is bombarded with a stream of electrons
- The electric current in AC circuit is given by the relation i-3 sinωt+4 cos ωt.
Topics: Motion in Straight Line
(93)
Subject: Physics
(2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
- In the half wave rectifier circuit operating from 50 Hz mains frequency,
- The drive shaft of an automobile rotates at 3600 rpm and transmits 80 HP
- A body oscillates with amplitude of 10 cm in a horizontal platform.
- A gas of monoatomic hydrogen is bombarded with a stream of electrons
- The electric current in AC circuit is given by the relation i-3 sinωt+4 cos ωt.
Topics: Motion in Straight Line (93)
Subject: Physics (2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
18000+ students are using NEETLab to improve their score. What about you?
Solve Previous Year MCQs, Mock Tests, Topicwise Practice Tests, Identify Weak Topics, Formula Flash cards and much more is available in NEETLab Android App to improve your NEET score.
Share this page with your friends
Leave a Reply