Practicing Success

Target Exam

CUET

Subject

Physics

Chapter

Laws of Motion

Question:

A metallic sphere is suspended on stationary wall with the help of a string. Forces as shown in the fig. are acting on the sphere. Which of the following statement is not correct?

Options:

$\vec{N} + \vec{T} + \vec{W}$ = 0

$T^2=N^2 + W^2$

T=N+W

N=Wtanθ

Correct Answer:

T=N+W

Explanation:

From the figure in equilibrium

Tsinθ=N
Tcosθ=W
⇒ tanθ = N/W​
N=Wtanθ

As body is in equilibrium net force is zero 

⇒ $\vec{N} + \vec{T} + \vec{W}$ = 0

Normal force N and Gravitational force W are at right angle so their resultant must balance tension force.

⇒ $T^2=N^2 + W^2$