Watch
Announcements
#1
Maybe I'm being dim but where is the resistance from I don't get it-
9:27 http://www.examsolutions.net/maths-r...tutorial-1.php
Thanks
0
#2
Bump
0
5 years ago
#3
The R is the "reaction" force which is the normal contact force that is applied perpendicular to the surfaces in contact...
0
5 years ago
#4
(Original post by MathMeister)
Maybe I'm being dim but where is the resistance from I don't get it-
9:27 http://www.examsolutions.net/maths-r...tutorial-1.php
Thanks
There is no resistance. The plane is smooth.
0
5 years ago
#5
Well in this problem there is no resistance, the only resistance is gravitational. This is called the 'conservation of mechanical energy'. So for this particular problem you could just let KE(gain)=PE(loss) or vice versa.

Or you could find the KE(gain) and PE(loss). This applies the 'work-energy principle'. That Work Done = change in energy.

So if we have KE(gain) and PE(loss), the total loss of energy = PE(loss) - KE(gain). The Work Done against resistance will be 0, since the resistance is 0 N. So PE(loss) - KE(gain) = 0 or PE(loss) = KE(gain) which is the same as the first example.

So when there is no non-gravitational resistance, using the conversation of mechanical energy. When there is non-gravitational resistance, use the work-energy principle!
0
X

new posts
Back
to top
Latest
My Feed

### Oops, nobody has postedin the last few hours.

Why not re-start the conversation?

see more

### See more of what you like onThe Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

### Poll

Join the discussion

Yes (103)
61.31%
No (65)
38.69%