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3 years ago

1- A 30 gram bullet travels at 300 m/s. How much kinetic energy does it have?

Physics

2 answers:

labwork [276]3 years ago

7 0

Answer:

1.35 kJ

Explanation:

KE = ½mv² = ½ × 0.030 kg × (300 m·s⁻¹)² = 1350 J = 1.35 kJ

madam [21]3 years ago

3 0

Given:-

Mass (m) of the bullet = 30 grams
Velocity of the bullet (v) = 300 m/s

To Find: Kinetic energy of the bullet.

We know,

Eₖ = ½mv²

where,

Eₖ = Kinetic energy,
m = Mass &
v = Velocity.

thus,

Eₖ = ½(30 g)(300 m/s)²

= (15 g)(90000 m²/s²)

= 1350000 g m²/s²

= 1350 kg m²/s²

= 1350 J

= 1.35 kJ (Ans.)

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