Gibbons, small Asian apes, move by brachiation, swinging below a handhold to move forward to the next handhold. A 9.1 kgkg gibbon has an arm length (hand to shoulder) of 0.60 mm. We can model its motion as that of a point mass swinging at the end of a 0.60-mm-long, massless rod. At the lowest point of its swing, the gibbon is moving at 3.3 m/s. Required:
What upward force must a branch provide to support the swinging gibbon?

254.345 N

Explanation:

Given that

Mass m = 9.1 kg

Velocity, v = 3.3 m/s

Radius, r = 0.6 m

Recall newton's second law of motion,

F = ma, where

F = Force exerted

m = mass of object

a = acceleration of object

Since the forces acting on this body are gravitational and tensile, we then have our F to be

F = T - mg

Also, we have our acceleration to be centripetal and thus,

a = v²/r

Remember that F = ma and F = T - mg. This means that

T - mg = ma.

Substituting the formula for a, we have

T - mg = mv²/r

On solving, we have

T = mv²/r + mg

T = m(v²/r + g)

If we then substitute the values we get from the question into it, we have

T = 9.1 (3.3²/0.6 + 9.8)

T = 9.1 (10.89/0.6 + 9.8)

T = 9.1 (18.15 + 9.8)

T = 9.1 * 27.95

T = 254.345 N

probably not if net force is zero

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.