Question

An object weighing 450 kg moving with a velocity of 15 m/s. find k
inetic
energy ​

Answer 1

Given :

Mass of the object, m = 450 Kg

Velocity of the object, v = 15m/s

To Find :

Kinetic Energy of the object

Solution :

Kinetic energy is directly proportional to the mass of the object and to the square of its velocity. It is scalar quantity .i.e.,

${ \leadsto{ \bf{K.E = \dfrac{1}{2}mv^2}}}$

so, Substituting all the given values in the formula

${ \leadsto{ \bf{K.E = \dfrac{1}{2} \times 450 \times {10}^{2} }}}$

${\leadsto{\bf{ KE = 225 × 225}}}$

${\leadsto{ \boxed{\bf{ KE = 4950 J}}}}$

Thus,the kinetic energy of the object is 4950J.

Remember !

SI unit of kinetic energy is Joules

Answer 2

Answer :

›»› The Kinetic energy of an object is 50625 J.

Given :

• Mass of an object = 450 kg.
• Velocity of an object = 15 m/s.

To Calculate :

• Kinetic energy of an object = ?

How to solve?

For solving this question let's first know about Kinetic energy.

• Kinetic energy is a scalar quantity.
• The SI unit of Kinetic energy is Joule.
• The CGS unit of Kinetic energy is erg.

To calculate the Kinetic energy of an body we use the equation of Kinetic energy.

The Kinetic energy equation is given as follows :

$\leadsto\bf{K.E = \dfrac{1}{2}m {v}^{2} }$

Here,

• K.E is the Kinetic energy.
• m is the Mass of an object.
• v is the Velocity of an object.

Units,

• The unit of Kinetic energy is Joule.
• The unit of Mass of kg.
• The unit of Velocity is m/s.

Calculation :

$\tt{:\implies \mathscr{K.E} = \dfrac{1}{2}m {v}^{2} }$

⠀

$\tt{:\implies \mathscr{K.E} = \dfrac{1}{2} \times 450 \times {15}^{2} }$

⠀

$\tt{:\implies \mathscr{K.E} = \dfrac{1}{ \cancel{ \: 2 \: }} \times \cancel{450} \times 625 }$

⠀

$\tt{:\implies \mathscr{K.E} = 225 \times 225}$

⠀

$\tt{:\implies \mathscr{K.E} = 225 \times 225}$

⠀

$\bf{:\implies \blue{\boxed{ \pink{\bf{\mathscr{K.E} = 50625}}}}}$

⠀

Hence, the Kinetic energy of an object is 50625 J.

⠀

⠀

$\qquad \boxed{\bf{\overline{\underline{\bigstar Some \: related \: formulae \bigstar}}}}$

⠀

❍ Linear moment = mg.

❍ Potential energy = mgh.

❍ Kinetic energy = ½mv²

Here,

• m is the Mass.
• g is the Acceleration due to gravity.
• v is the Velocity.

Units,

• The unit of Mass is kg.
• The unit of Acceleration due to gravity is m/s².
• The unit of Velocity is m/s.