How Far Did the Robber's Car Travel in 6 Seconds with a Forgotten Brick of Gold?

  • Thread starter Thread starter jk2455
  • Start date Start date
  • Tags Tags
    Displacement
AI Thread Summary
The discussion centers on calculating the distance a car travels during a bank robbery when it accelerates from rest for 6 seconds, with a brick of gold on the roof. The problem involves determining the car's acceleration using the coefficient of static friction (µs = 0.4) and applying the equations of motion. Participants suggest equating the frictional force to the force acting on the brick to find acceleration. The final calculated distance traveled by the car in this scenario is 70.56 meters. The conversation emphasizes the importance of understanding friction and motion equations in solving the problem.
jk2455
Messages
12
Reaction score
0

Homework Statement


During a bank robbery, one of the gangsters forgets a brick of gold on the roof of the
car. Assuming that the car accelerates from rest with a constant acceleration, and that the
brick was on the point of slipping, throughout the acceleration, how far did the car travel
in the first 6s if µs = 0.4?

(the answer is 70.56m)

The Attempt at a Solution


1. Homework Statement [/

givens:
x direction---> a=? delta x=? initial velocity=0 final velocity=?
y direction---> a=0 delta y=0 " " " = 0
mu=o.4 t=6

Homework Equations



x=(initial velocity)( time )+ 1/2 (a)(t)

The Attempt at a Solution


Homework Statement


Homework Equations


The Attempt at a Solution

 
Last edited:
Physics news on Phys.org
you have to attempt a solution first.
 
but i am not sure where to start could someone give me a hint
 
I am assuming the friction to be only between the car and the block.
say the frictional force is f=µs*m*g. but this has to be equal to the force acting on it.
so equate it to m*a and get a value for the acceleration.

Use the equations of motion where you know a, u, and t...and hence find s.
 
thanks :)
 
you'r welcome! :smile:
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Back
Top