Question

While driving on the freeway at 110 km h, you pass a truck whose total length you estimate at 25 m. If it takes you, in the driver’s seat, 5.5 s to pass from the rear of the truck to its front, what is the truck’s speed relative to the road?

Answer 1

Normally, it would take 9/11 seconds to pass the truck if it is stationary. From that, I got it takes the driver 4.68 additional seconds to pass it than if it was stationary.

110 = other_rate + 4.68 (This isn't right, and I don't think it is, but it is the closest equation I can think of.)

Answer 2

If the answer is 26 m/s or 93.6 Km/h .. I can help you!

Answer 3

@DanielHendrycks

Answer 4

Do you have the answer?

Answer 5

Let the velocity of truck relative to ground be v. Find the relative velocity.
Displacement= relative velocity \(\times\) time..

Convert Km/h into m/s since you have all other values in SI.

Answer 6

Sorry. I'm here. Give me a second to read.

Answer 7

It is 26 m/s

Answer 8

Ok then do as i have mentioned!

Answer 9

The truck isn't going to make and distance from the ground (it will keep touching it). Do you mean the point we should be speaking relative to is a place on the ground?

Answer 10

I don't get what you are trying to say!

Answer 11

You are saying it should be relative to the ground right?

Answer 12

Ok i am explaining it all again:

Answer 13

Let the velocity of truck relative to ground be v.

Now, find the velocity of truck relative to you..

Now, Displacement of truck relative to you= velocity of truck relative to you \(\times\) time

In this case, the displacement of truck relative to you is 25 m.

Answer 14

25 = v relative to me * 5.5; therefore v relative to me is 25/5.5 or 4.54. That's not right.

Answer 15

Velocity of truck relative to you=your velocity-velocity of truck relative to ground= (30.55-v) m/s
Note: 110 Km/h=30.55 m/s

Now,
25=(30.55-v)* 5.5
Or, v=26 m/s

Answer 16

Got it! I'll make note of this problem.

Answer 17

RAPE JOKE