MY CART (5)

Use Coupon: CART20 and get 20% off on all online Study Material

ITEM
DETAILS
MRP
DISCOUNT
FINAL PRICE
Total Price: R

There are no items in this cart.
Continue Shopping
Menu
Shobhit Gupta Grade: 12
        

A driver applies brakes to the vehicle on seeing traffic signal 400 m ahead .At time of applying the brakes vehicle was moving with 15m/s and then starts retarding with 0.3 m/s^2 .The distance of vehicle after 1 min from traffic light A : 25 mB : 375mC : 360mD ; 40m

7 years ago

Answers : (2)

Ramesh V
70 Points
										

The equations of motion are:


Using relation V2 - u2 = 2*a*S


      and Using relation V - U = a*t     V:final vel.  U: initial vel.  a:accln  S:distance travelled


The distance travelled before car comes to rest is V=0, U = 15,a=-0.3


S=225/0.6 =375mts


The car comes to rest even before reaching traffic signal.


It comes to rest at 25m ahead traffic signal.


The time taken by car to come to rest is : V/a = 15/0.3 = 50 sec


In 50 seconds car comes to rest


so after 1 min,also car stays 25m ahead of traffic post


option A

7 years ago
askIITianexpert IITDelhi
8 Points
										

Distance travelled by vehicle in 1 min.(=60 sec.) after applying brakes=15*60-(0.3)*602 = -180mtrs.(s=ut+1/2at2)                                    


 (-ve) value above indicates that vehicle must've stopped due to brake action in less than 1 min.


So using,


                v2=u2+2as;s=(15)2 /(2*0.3)=375m


So answer would be A:25m(400-375)

7 years ago
Think You Can Provide A Better Answer ?
Answer & Earn Cool Goodies
  • Complete Physics Course - Class 12
  • OFFERED PRICE: R 2,600
  • View Details
  • Complete Physics Course - Class 11
  • OFFERED PRICE: R 2,800
  • View Details

Ask Experts

Have any Question? Ask Experts

Post Question

 
 
Answer ‘n’ Earn
Attractive Gift
Vouchers
To Win!!! Click Here for details