relative motion doubt
an elevator whose floor to ceiling distance is 2.7m starts ascending with accn 1.2m/s^2. two sec after is starts a bolt begins to fall from the ceiling of the elevator. find the distance and displacement of bolt wrt ground
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@Gyro Gearloose
Note for OP
+solved @user to close the thread when your doubt is solved. Mention the user who helped you solve the doubt. This will be added to their stats.what did you try so far
i got bolts freefall time as 0.7s
then i figured at t=0 bolt is 2.7m above the ground
at t=2 elevator floor is 2.4m above ground and bolt is 2.4+2.7m above the ground
at t=2.7 bolt is 4.37 m above the ground
is that the complete question?
first part was finding out time of free fall but i figured that out
I'm assuming the displacement and distance are once the bolt hits the floor of the elevator?
yep
"the distance and displacement covered by bolt during the fall wrt ground"
I got 1.65 m which is probably wrong
displacement is 1.31 with g=9.8 , given in the book
Ah I took 10
Nope I got it wrong
anyone ???
The bolt has an effective acceleration of 11m/s^2 with respect to the elevator
use s=1/2 at^2 to find time
In this time the bolt has travelled -2.7 metres downward with respect to the elevator
find the distance travelled by the elevator in this time and add it
can you help in reference to this
so basically height of elevator floor from ground at t=2.7
i got this as 4.37
No, the difference between the heights at t=2 and t=2.7
that comes out to be 1.9m
my bad, use s=vt-1/2gt^2
and then it's the same steps
Can you please share a written solution
First, we find the time taken
Comrade Rock Astley
u is 2.4 m/s
a is the relative accleration of the ball wrt. the elevator
You can find t here
Find the distance travelled by the elevator in that time
so basically this
now this displacement is positive
ball falling onto the elevator floor is negative displacement
add with signs to get your total displacement
If you're stuck anywhere you can refer to this solution too
An elevator car whose floor to ceiling distance is equal to 2.7 m s...
An elevator car whose floor to ceiling distance is equal to 2.7 m starts ascending with constant acceleration 1.2 m / s 2 .2 s after the start, a bolt begins falling from the ceiling of the car. Find:a the bolt's free fall time;b the displacement and the distance covered by the bolt during the free fall in the reference frame fixed to the ground...
+solved @Comrade Rock Astley
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