| ⇦ | 
| ⇨ |
A body covers 200 cm in the first 2 seconds and 220 cm in the next 4 seconds. The velocity of the body at the end of the 7th second is
Options
(a) 10 cm/s
(b) 20 cm/s
(c) 5 cm/s
(d) 30 cm/s
Correct Answer:
10 cm/s
Explanation:
Let u and a be the initial velocity and uniform acceleration of the body.
Using kinematic equation, S = ut + (1/2) at²
.·. 200 = u × 2 + (1/2) a × 2²
⇒ 100 = u + a ——-(i)
Also 420 = 6u + (1/2) a × 6²
⇒ 70 = u + 3a ——-(ii)
Solving equation (i) and (ii), we get u = 115 cms⁻¹, a = -15 cms⁻²
Using equation, v = u + at .·. v = 115 + (-15) × 7 = 10 cms⁻¹
Related Questions: - Radius of a soap bubble is increased from R to 2R. Work done in this process
- A 120 m long train is moving in a direction with speed 20 m/s.A train B moving
- A capacitor of 10 µF charged upto 250 volt is connected in parallel with another
- If the alternating current I=I₁ cosωt+I₂ sinωt, then the rms current is given by
- Monochromatic radiation emitted when electron on hydrogen atom
Topics: Motion in Straight Line
(93)
Subject: Physics
(2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
- Radius of a soap bubble is increased from R to 2R. Work done in this process
- A 120 m long train is moving in a direction with speed 20 m/s.A train B moving
- A capacitor of 10 µF charged upto 250 volt is connected in parallel with another
- If the alternating current I=I₁ cosωt+I₂ sinωt, then the rms current is given by
- Monochromatic radiation emitted when electron on hydrogen atom
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