A ball of mass m is connected with the string AB and BC respectively a shown in the figure. Now string AB is cut Answer the following questions

Question

Comprehension Type:

Paragraph: A ball of mass m is connected with the string AB and BC respectively a shown in the figure. Now string AB is cut Answer the following questions

(i) Tension in the string AB and BC respectively the string AB is cut 

(A) mg cotB, mg cosB 

(B) mg tanB, mg cosB 

(C) mg tanB, mg secB 

(D) mg cotB, mg secB 

(ii) Tension in the string BC just after the string AB is cut 

(A) mg sinB 

(B) mg cosB 

(C) mg tanB 

(D)mg secB

(iii) If string BC is cut instead of AB, what is the tension in the string AB just after 

(A) mg cosB 

(B) mg tanB 

(C) mg sinB 

(D) zero

(iv) If the whole system is placed in an automobile, what is the acceleration required to be given to it so that even after cutting the string AB, it remains in the same position 

(A) g tanB, right ward 

(B) g cotB, right ward 

(C) g tanB, left ward 

(D) g cotB, left ward

Answer 1

(i) (C) mg tanB, mg secB

(ii) (B) mg cosB

(iii) (D) zero

(iv) (A) g tanB, rightward

Now when string BC is cut;

Mass ‘m’ will just have force fall. Hence tension in string AB is zero.

Now suppose it is keep in a moving automobile;

In automobile’s frame of reference, there is a pseudo force acting on the mass.

The resultant force should be along BC.

Since its acting leftwards, the vehicle should move rightwards.

Answer 2

(i) (C) mg tanB, mg secB

(ii) (B) mg cosB

(iii) (D) zero

(iv) (A) g tanB, right ward