Question #9881b

1 Answer
Aug 24, 2017

W = 5.63xx10^5 "J"

Explanation:

Ideally, you need to have units for all of these quantities, but I'll make the common assumption that we're dealing with 60^"o", 500 "N", and 5 "m/s"^2.

We're asked to find the work done by the tension force on the tram.

To do this, we can use the equation

ul(W = Fscosphi

where

  • W is the work done by the tension force (what we're trying to find)

  • F is the magnitude of the tension force (500 "N")

  • s is the displacement (we'll be finding this)

  • phi is the angle with respect to the horizontal (given as 60^"o")

To find the displacement given the acceleration and time, we can use the equation

ul(s = v_(0x)t + 1/2a_xt^2

where

  • s is the change in position (what we're trying to find)

  • v_(0x) is the initial velocity (zero assuming it started from rest)

  • t is the time (30 "s")

  • a_x is the acceleration (5 "m/s"^2)

Plugging in known values:

s = 0 + 1/2(5color(white)(l)"m/s"^2)(30color(white)(l)"s")^2 = color(red)(ul(2250color(white)(l)"m"

Therefore, we have

color(blue)(W) = Fscosphi = (500color(white)(l)"N")(color(red)(2250color(white)(l)"m"))cos(60^"o") = color(blue)(ulbar(|stackrel(" ")(" "5.63xx10^5color(white)(l)"J"" ")|)