Westonci.ca is your trusted source for accurate answers to all your questions. Join our community and start learning today! Experience the convenience of finding accurate answers to your questions from knowledgeable experts on our platform. Connect with a community of professionals ready to help you find accurate solutions to your questions quickly and efficiently.

A boy and girl are running with the same speed.if the mass of the boy is 20 times that of girl find the kinectic energy

Sagot :

Answer:

The kinetic energy of the boy is 20 times that of the kinetic energy of the girl.

Explanation:

It is given that,

The mass of the boy is 20 times that of girl.

Let [tex]m_b[/tex] and [tex]m_g[/tex] are the mases of boy and the girls.

A boy and girl are running with the same speed.

The formula for the kinetic energy is given by :

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

Where m is mass and v is speed

As speed is same for both boy and girl.

Kinetic energy of a girl,

[tex]K_g=\dfrac{1}{2}m_gv^2[/tex] ...(1)

As [tex]m_b=20m_g[/tex]

Kinetic energy of a boy,

[tex]K_b=\dfrac{1}{2}m_bv^2\\\\=\dfrac{1}{2}\times 20m_g\times v^2\ ....(2)[/tex]

From equation (1) and (2) :

[tex]\dfrac{K_g}{K_b}=\dfrac{\dfrac{1}{2}m_gv^2}{\dfrac{1}{2}m_bv^2}\\\\=\dfrac{\dfrac{1}{2}m_gv^2}{\dfrac{1}{2}\times 20 m_gv^2}\\\\\dfrac{K_g}{K_b}=\dfrac{1}{20}\\\\K_b=20K_g[/tex]

So, the kinetic energy of the boy is 20 times that of the kinetic energy of the girl. Hence, this is the required solution.