Question

a hammer of mass 1 kg Falls freely on a name placed on a piece of wood if it falls from a height of 1m how much kinetic energy will have just for eating dinner at 1 gram equal to 10 metre per second ​

Answer 1

Explanation:

Kinetic energy of an object is the energy possessed by the object due to its state of motion.

The kinetic energy of an object can be calculated by the formula :

K = 1/2 × mass × velocity²

K = 1/2 m v²

Given info :

Mass of the hammer ( m ) = 1 kg .

Height from which it falls ( h ) = 1 m .

We know by the Laws of Motion :

v² = u² + 2 g h

Initial velocity of the hammer ( u ) = 0 m/s

Acceleration due to gravity ( g ) = 10 m/s²

v² = 0 + 2 × 10 m/s² × 1 m

⇒ v² = 20 m²/s² .

Now we know that :

K = 1/2 × m v²

⇒ K = 1/2 × 1 kg × 20 m²/s² [ Putting the values ]

⇒ K = 10 kg m²/s²

⇒ K = 10 J

The kinetic energy will be 10 J .

Answer 2

Given that, a hammer of mass 1 kg falls freely on a name placed on a piece of wood.

{ Mass i.e. m of the hammer is 1 kg }

Also given that, the height from were hammer falls is 1 m.

{ Height i.e. h is 1 m}

We have to find the Kinetic Energy (K.E.)

Now,

K.E. = 1/2 mv²

K.E. = 1/2 × 1 × v²

Also,

v² - u² = 2as

Here, s = height = 1 m

Initial velocity (u) of the hammer is 0 m/s and Acceleration due to gravity (a) is 9.8 m/s². (Approx. 10 m/s²)

→ v² - (0)² = 2 × 10 × 1

→ v² = 20

→ v = √20

Therefore,

K.E. = 1/2 × 1 × 20 { As, v² = 20 }

K.E. = 10 J