A 50g ball is released from rest 1.0 above the bottom of thetrack
shown. It rolls down a straight 30o segment, thenback up
a parabolic segment whose shape is given byy=(1/4)x2 ,
where x and y are in m. How high will theball go on the right
before reversing direction and rolling backdown?

Respuesta :

Answer:

The maximum height of the ball is 2 m.

Explanation:

Given that,

Mass of ball = 50 g

Height = 1.0 m

Angle = 30°

The equation is

[tex]y=\dfrac{1}{4}x^2[/tex]

We need to calculate the velocity

Using conservation of energy

[tex]\Delta U_{i}+\Delta K_{i}=\Delta K_{f}+\Delta U_{f}[/tex]

Here, ball at rest so initial kinetic energy is zero and at the bottom the potential energy is zero

[tex]\Delta U_{i}=\Delta K_{f}[/tex]

Put the value into the formula

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

Put the value into the formula

[tex]50\times10^{-3}\times9.8\times1.0=\dfrac{1}{2}\times50\times10^{-3}\times v^2[/tex]

[tex]v^2=\dfrac{2\times50\times10^{-3}\times9.8\times1.0}{50\times10^{-3}}[/tex]

[tex]v=\sqrt{19.6}[/tex]

[tex]v=4.42\ m/s[/tex]

We need to calculate the maximum height of the ball

Using again conservation of energy

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

Here, h = y highest point

Put the value into the formula

[tex]\dfrac{1}{2}\times50\times10^{-3}\times(4.42)^2=50\times10^{-3}\times9.8\times h[/tex]

[tex]y=\dfrac{0.5\times(4.42)^2}{9.8}[/tex]

[tex]y=0.996\ m[/tex]

Put the value of y in the given equation

[tex]y=\dfrac{1}{4}x^2[/tex]

[tex]x^2=4\times0.996[/tex]

[tex]x=\sqrt{4\times0.996}[/tex]

[tex]x=1.99\ m\ \approx 2 m[/tex]

Hence, The maximum height of the ball is 2 m.