Sunday

March 29, 2015

March 29, 2015

Posted by **Emeka** on Tuesday, November 15, 2011 at 5:42am.

- physics -
**Dr Russ**, Tuesday, November 15, 2011 at 5:55am"A load of mass 80kg fell dwn from d floor of a lorry whch is 1.2m high.calculate wrk dne by gravity on d land "

If you can write the question in normal plain english you are more likely to get a correct answer. You should also get in the habit of correctly spacing number and units as this will then come automatically when you type or write.

Assuming that you need to calcualte the work done when a mass of 80 kg falls 1.2 m under gravity (assume that g = 9.8 m s^-2).

Force on the mass is

mass x acceleration =

1.8 kg x 9.8 m s^-2 = 17.64 N

work done is

force x distance

= 17.64 N x 1.2 m = 21.168 N m

or 21 N m to 2 sig figs (assuming that the mass 80 kg is to 2 sig figs).

**Answer this Question**

**Related Questions**

mechanics-physics - A lorry of mass 1000kg moving initially at 10m/s increases ...

.physics - correction of question. A lorry of mass 1000kg moving initially at ...

math - Two Lorries A and B ferry goods between two towns which are 3120 km apart...

math - The distance between towns M and N is 280 km. A car and a lorry travel ...

Physics - A 4.80kg cat leaps from the floor to the top of a 94.0-cm-high table. ...

Science - A lorry has a mass of 5640kg and accelerates uniformly from rest to ...

Engineering science - A lorry has a mass of 5640kg and accelerates uniformly ...

physics - An autographed baseball rolls off of a 1.3 m high desk and strikes the...

physics - A 72 g baseball rolls off a 1.5 m high table and strikes the floor a ...

Physics - An autographed baseball rolls off of a 0.85 m high desk and strikes ...