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What is resistive force?

A bullet of mass 20 gm is shot from a gun with velocity 200ms^-1. The bullet stops after penetrating 6cm of a wood.
Determine resistive force of the bullet.​

User Keaton
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2 Answers

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Final answer:

The resistive force, also known as the stopping force, is the force that opposes the motion of an object. In this case, we can determine the resistive force of the bullet by calculating the deceleration and using the formula: Stopping force = mass x deceleration. The resistive force of the bullet is -4000 N.

Step-by-step explanation:

The resistive force, also known as the stopping force, is the force that opposes the motion of an object. In this case, the resistive force is the force exerted by the wood to stop the bullet. To determine the resistive force of the bullet, we can use the formula:

Stopping force = mass of the bullet x deceleration

First, let's convert the mass of the bullet from grams to kilograms: 20 gm = 0.02 kg.

Next, we can calculate the deceleration using the equation: final velocity squared = initial velocity squared + 2 x acceleration x distance.

Given that the initial velocity is 200 m/s, final velocity is 0 m/s, and distance is 6 cm (which is 0.06 m), we can solve for the deceleration. Rearranging the equation, we have: acceleration = (final velocity squared - initial velocity squared) / (2 x distance).

Plugging in the values, we get: acceleration = (0 m/s - (200 m/s)^2) / (2 x 0.06 m).

Calculating this, we find that the deceleration is -200000 m/s^2.

Finally, we can calculate the stopping force using the formula: Stopping force = mass of the bullet x deceleration.

Plugging in the values, we have: Stopping force = 0.02 kg x -200000 m/s^2. Calculating this, we find that the resistive force of the bullet is -4000 N.

User Craken
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Answer:

In physics, resistive force is a force, or the vector sum of numerous forces, whose direction is opposite to the motion of a body, and may refer to: Friction, during sliding and/or rolling.

A 7.80-g bullet moving at 575 m/s penetrates a tree trunk to a depth of 5.50 cm. (a) Use work and energy considerations to find the average frictional force that stops the bullet. (b) Assuming the frictional force is constant, determine how much time elapses between the moment the bullet enters the tree and the moment it stops moving.

Step-by-step explanation:

User Kamaria
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