Question

A lead of mass 2kg, travelling with a velocity of 20ms–¹,comes to rest after penetrating 20m in a still target. Find the average acceleration (a) of the bullet and resistive force (f) applied by the target

Answer 1

GiveN :

• Mass (m) = 2 kg
• Initial velocity (u) = 20 m/s
• Final velocity (v) = 0 m/s
• Distance travelled = 20 m

To FinD :

• Acceleration
• Force

SolutioN :

Use 3rd equation of Motion :

⇒a = (v² - u²)/2s

⇒a = (0² - 20²)/2*20

⇒a = -400/40

⇒a = - 10 m/s²

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Formula For Calculating Force :

⇒F = ma

⇒F = 2 * -10

⇒F = -20 N