A car accelerates from rest at constant rate for first 10s and covers a distance x.

⇦

⇨

A car accelerates from rest at constant rate for first 10s and covers a distance x.  It covers a distance y in next 10s at the same acceleration.Which of the following is true?

Options

(a) x=3y
(b) y=3x
(c) x=y
(d) y=2x

Correct Answer:

y=3x

Explanation:

From equation of motion, we have S = ut+(1/2) at²
where, u=initial velocity, t=time, a=acceleration.
Since, car accelerates from rest u=0, t=10s
.·. s = 0 + (1/2) x a x (10)² ( .·. S=x)
x = (1/2) x a x (10)²
then, a = 2x/(10)²
Also
v = u + at Where, v is the final velocity.
= 0 + [2x/(10)²] x 10
= 2x/10ms
In the next 10s car moves with constant acceleration and with initial
velocity u = 2x/10 m/s
.·. S = (2x/10) x 10 + (1/2) x [2x/(10)²] x (10)²
= 2x + x when S=y
y = 3x
x and y is the two different distance covers a car with same time.

Related Questions:

1. An electric dipole of dipole moment p is aligned parallel to a uniform electric field E
2. The current flowing through a lamp marked as 50 W and 250 V is
3. For the normal eye, the cornea of eye provides a converging power of 40D
4. A body projected vertically from the earth reaches a height equal to earth’s radius
5. X-ray beam can be deflected by

Difficulty Level: Easy (1008)
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