posted by Leah on .
A pendulum consists of an object of mass m = 1 kg swinging on a massless string of length l = 258 cm. The object has a speed of 1.6 m/s when it passes through its lowest point. What is the greatest angle with the vertical that the string makes during the motion of the object?
So I tried doing this by calculating GPE = mgh
So does this mean KE = 25.3?
However I don't even use the velocity at the lowest point, I am extremely confused...help =S
find the KE at the lowest point: 1/2 m v^2
Now, take that value,and set it equal to mgh
That is the height the bob goes up.
Now, angle= arccos(l-h)/l
make your drawing, and confirm that.
Yes I see what you're saying after drawing the diagram...So for the first bit we just use plain substitution of GPE formulas and second bit is trig.
=) thanks that seemed easier than i thought.