Question

11. A physical therapist is using a wide elastic band to help a

patient strengthen his knee after surgery. At the patient's
current stage of therapy, he should not exert more than 20
kilograms weight of force. The band being used for this
therapy exerts a force of 40 grams of weight for every
millimeter it is extended. The relationship between force
applied and the distance the band is extended is linear.
What is the maximum distance the therapist should allow
the patient to extend the band?
(A) 5 millimeters
(B) 5 centimeters
(C) 5 decimeters
(D) 80 centimeters​

Answer 1

(C) 5 decimeters

Explanation:

A therapist is using an elastic band to strengthen a patient's knee after surgery.

The patient's knee can tolerate a maximum of 20 kg i.e. 20000 gm weight of force.

If the elastic band provides 40 gm of weight force for every millimeter of its extension.

then this can be extended up to
`(20000)/(40) =500` millimeters, which is equal to 5 decimeters.

Therefore, option c is correct. (Answer)