Thursday

April 24, 2014

April 24, 2014

Posted by **Jen** on Monday, September 11, 2006 at 4:54pm.

a) how far does teh cab move while accelerating to full speed from rest?

b) How long does it take to make the nonstop trip 190m start and end at rest?

What would the equation be for this problem?

There is no single equation to plug into. You need to do this problem, like many in enginering and physocs, one step at a time.

First calculate the time it takes to accelerate to maximum speed and the (equal) time that it takes to decelerate from that speed to zero. That time is

t = Vmax/a = (305 m/min)*(1/60min/s)/1.22 m/s^2 = 4.17 s

So the elevator spends 8.34 s accelerating and decelerating. Figure out how far in goes during each of those intervals. That distance is

X1 = X3 = (1/2) a t^2 = 10.6 m

That is the answer to part (a) of your question. For part (b), calculate how much of the total run is traversed at constant velocity. That would be

X2 = 190 - (2)(10.6) = 168.8 m

For the total transit time, add the time spent accelerating, decelerating, and the time spend traveling at maximum speed. The latter time is just

t2 = 168.8 m/305 m/min = 0.553 min = 33.2 s.

Add 2t to that for your answer.

**Related Questions**

physics - A certain elevator cab has a total run of 204 m and a maximum speed is...

physics - "A cab driver picks up a customer and delivers her 3.31 km away, ...

physics - An elevator cab in the New York Marriott Marquis has a mass of 4.96 x...

physics - A fully loaded, slow-moving freight elevator has a cab with a total ...

physics - a 3200-lb elevator cab is supported by a cable in which the maximum ...

Physics - fully loaded, slow-moving freight elevator has a cab with a total ...

Physics - A fully loaded, slow-moving freight elevator has a cab with a total ...

physics - In a large hotel, a fast elevator takes you from the ground floor to ...

physics - An elevator is initially moving upward at a speed of 12.84 m/s. The ...

Physics - An elevator is initially moving upward at a speed of 11.04 m/s. The ...