A small 0.13 kg metal ball is tied to a very light (essentially massless) string that is 0.70 m long. The string is attached to the ceiling so as to form a pendulum. The pendulum is set into motion by releasing it from rest at an angle of 50 ∘ with the vertical.
A) What is the speed of the ball when it reaches the bottom of the arc?
B)What is the centripetal acceleration of the ball at this point?
C)What is the tension in the string at this point?

Respuesta :

Answer:

Explanation:

Let l be th length of pendulum

loss of height

= mg ( l - l cos50)

= mg l ( 1-cos50)

1/2 mv² = mgl ( 1-cos50)

v = √[2gl( 1- cos50)]

= √( 2 x 9.8 x .7 x ( 1-cos50)

= 2.2 m / s

speed at the bottom = 2.2 m /s

b )

centripetal acceleration

= v² / r

= 2.2 x 2.2 / .7

= 6.9 m /s²

C )

If T be the tension

T - mg = mv² / r

T = mg + mv² / r

= .13 X 9.8 + .13 X 6.9

= 2.17 N

The speed of the ball when it reaches the bottom of the arc is 2.2 m/sec, the centripetal acceleration of the ball at this point is 6.91 m/[tex]\rm sec^2[/tex], and the tension in the string at this point is 2.1723 N.

Given :

  • A small 0.13 kg metal ball is tied to a very light (essentially massless) string that is 0.70 m long.
  • The string is attached to the ceiling so as to form a pendulum. The pendulum is set into motion by releasing it from rest at an angle of 50 ∘ with the vertical.

A) First, determine the distance covered by the pendulum that is 'h'.

[tex]\rm h = mg(l - l\;cos\theta )[/tex]

[tex]\rm h = mgl(1-cos\theta )[/tex]

Now, from kinematics the displacement is given by:

[tex]\rm S = \dfrac{1}{2}mv^2[/tex]

[tex]\rm mgl(1-cos\theta) = \dfrac{1}{2}mv^2[/tex]

[tex]\rm v = \sqrt{2gl(1-cos\theta )}[/tex]

Now, substitute the value of known terms in the above equation.

[tex]\rm v = \sqrt{2\times 9.8 \times 0.7(1-cos50 )}[/tex]

v = 2.2 m/sec

So, the speed of the pendulum at the bottom is 2.2m/sec.

B) The formula of the centripetal acceleration is given by:

[tex]\rm a = \dfrac{v^2}{r}[/tex]

[tex]a = \dfrac{(2.2)^2}{0.7}[/tex]

[tex]\rm a = 6.91m/sec^2[/tex]

C) Let 'T' be the tension then:

[tex]\rm T-mg = \dfrac{mv^2}{r}[/tex]

[tex]\rm T = 0.13\times 9.8+0.13\times 6.91[/tex]

T = 1.274 + 0.8983

T = 2.1723 N

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https://brainly.com/question/11048442