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. What is the energy of He⁺ electron in first orbit?
2. An object is placed 30 cm away from a convex lens of focal length 10 cm and a sharp
3. A radioactive substance contains 10000 nuclei and its halflife period is 20 days
4. Slope of PV and V for an isobaric process will be
5. The inductive reactance of an inductor of 1/π henry at 50 Hz frequency is

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