Question

an object is hanging by a string from your rear view mirror. while you are decelerating at a constant rate from 25 m/s to rest in 6.0 s, a) what angle does the string make with the vertical, and b) is it toward the windshield or away from it?

Answer 1

yes

Answer 2

do u no how to solve it

Answer 3

Find the rate of acceleration using: decelerating at a constant rate from 25 m/s to rest in 6.0 s

Then draw a free body diagram, remember the net horizontal force on the object is due to the above acceleration.

Answer 4

can u show me how

Answer 5

@besmir13
Do you know the concept of relative motion ??

Answer 6

actually no cus the professor just explained the chapter

Answer 7

acceleration will be (final velocity-initial velocity)/6 seconds, horizontally

gravitational acceleration is -9.8 m/s^2, vertically

net acceleration vector will be sum of these two vectors

Answer 8

Tension is T, acceleration is a from above, angle is x

vertical forces must be balanced so net force is zero, so:
mg = Tcos(x) (the Tcos(x) is the vertical component of tension)

Horizontal force is provided by the horizontal component of tension:
net F = Tsin(x)
ma = Tsin(x)

Now solve the two equations (use substitution, solve one of them for T):

mg = Tcos(x) ..... solve for T = mg/cos(x)
ma = Tsin(x)

You should get:
tan(x) = a/g

Solve for angle x.