Now the friends are ready to tackle a homework problem. A pulse is sent traveling along a rope under a tension of 29 N whose mass per unit length abruptly changes, from 19 kg/m to 45 kg/m. The length of the rope is 2.5 m for the first section and 2.8 m for the second, and the second rope is rigidly fixed to a wall. Two pulses will eventually be detected at the origin: the pulse that was reflected from the medium discontinuity and the pulse that was originally transmitted, which hits the wall and is reflected back and transmitted through the first rope. What is the time difference, Δt, between the two pulses detected at the origin? s

The time difference is 2.97 sec.

Explanation:

Given that,

Tension = 29 N

Mass per unit length

Mass per unit length

Length of first section = 2.5 m

Length of second section = 2.8 m

We need to total distance of first pulse

Using formula for distance

We need to total distance of second pulse

Using formula for distance

We need to calculate the speed of pulse in the first string

Using formula of speed

Put the value into the formula

We need to calculate the speed of pulse in the second string

Using formula of speed

Put the value into the formula

We need to calculate the time for first pulse

Using formula of time

Put the value into the formula

We need to calculate the time for second pulse

Using formula of time

Put the value into the formula

We need to calculate the time difference

Using formula of time difference

Put the value into the formula

Hence, The time difference is 2.97 sec.

! 55 !  

write a paragraph or story to explain the transformation between potential and kinetic energy as shown in your picture or model.  

you should have at least 5 complete sentences with a main idea and supporting details.  

you must include the following words:  

potential energy

kinetic energy

mechanical energy

conservation of energy

dude, this is hard lol : ))

it doesn't. it was imagined up in the middle ages.