Question

An infant throws 7 g of applesauce at a velocity of 0.5 m/s. All of the applesauce collides with a nearby wall and sticks to it. What is the decrease in kinetic energy of the applesauce?

Answer 1

Answer:

Δ KE = - 8.75 x 10⁻⁴ J

Explanation:

given,

mass of applesauce = 7 g = 0.007 Kg

initial velocity, u = 0.5 m/s

final velocity, v = 0 m/s

Decrease in kinetic energy = ?

initial kinetic energy

$KE_1=\dfrac{1}{2}mu^2$

$KE_1=\dfrac{1}{2}\times 0.007 \times 0.5^2$

      KE₁ = 8.75 x 10⁻⁴ J

final kinetic energy

$KE_2=\dfrac{1}{2}mv^2$

$KE_2=\dfrac{1}{2}\times 0.007 \times 0^2$

      KE₂ =0 J

Decrease in kinetic energy

Δ KE =  KE₂ - KE₁

Δ KE = 0 - 8.75 x 10⁻⁴

Δ KE = - 8.75 x 10⁻⁴ J

decrease in kinetic energy of the applesauce is equal to  8.75 x 10⁻⁴ J