1800-150-456-789
FlagBACK
Flag Mechanics> consider a car moving along a straight ho...
question mark

consider a car moving along a straight horizontal road with the speed of 72km/hr. if the coefficientof static friction between the tyre and the road is 0.5 , the shortest distance in which the car can be stopped is (g=10m/s^2)a) 30mb)40mc)72md)20m

gurnoor kaur , 6 Years ago
Grade 9
anser 1 Answers
Arun

Last Activity: 6 Years ago

Let ‘m’ be the mass of the vehicle. So, frictional force experienced by the vehicle on its tyres is, f = µmg

So, the acceleration of the vehicle due to this frictional force is, a = -µg (acceleration is directed opposite to the motion of the vehicle)

Now using,

v2 = u2 + 2as

=> 0 = v2 - 2 µgs

[initial velocity = v, final velocity = 0]

So, s = v2/(2µg)

 

v = 72 *5/18 = 20 m/sec

 

Hence

S = 400 /2 * 0.5 *10 = 40 m

 

Regards

Arun (askIITians forum expert)

Provide a better Answer & Earn Cool Goodies

Enter text here...
star
LIVE ONLINE CLASSES

Prepraring for the competition made easy just by live online class.

tv

Full Live Access

material

Study Material

removal

Live Doubts Solving

assignment

Daily Class Assignments


Ask a Doubt

Get your questions answered by the expert for free

Enter text here...

Other Related Questions on mechanics

question mark
A metal strip clamped at one end vibrates with a frequency of 20 Hz and amplitude of 5 mmat the free end, where a small mass of 2 g is positioned. determine(i) The velocity of the end when passing through the zero position(ii) The acceleration at maximum displacement(iii) The maximum kinetic energy of the mass
mechanics
2 Answers Available

Last Activity: 2 Years ago

question mark
An object of mass m = 0.25 kg oscillates in a fluid at the end of a vertical spring of springconstant kH = 85 N/m, see Fig.1. The effect of the fluid resistance is governed by thedamping constant b = 0.07kg/s.(i) Find the period of the damped oscillation.(ii) By what percentage does the amplitude of the oscillation decrease in each cycle?
mechanics
1 Answer Available

Last Activity: 2 Years ago

question mark
If a=x² find the displacement at t =3sec if body velocity at t= 0 sec is 0
mechanics
1 Answer Available

Last Activity: 2 Years ago

question mark
A particle is traveling in a circle of radius R =2.5m and with an angular velocity of 10 rad/s. What is the centripetal acceleration of the particle? The particle begins to slow down with an angular acceleration of -1 rad/s2. After 5 seconds, what is the centripetal acceleration and the tangential acceleration fo the particle?
mechanics
1 Answer Available

Last Activity: 2 Years ago

question mark
If the acceleration of block A is 5 m/s^2Find the acceleration of block B
mechanics
1 Answer Available

Last Activity: 2 Years ago