How do you calculate deceleration due to resistance?

In summary, deceleration due to resistance is the decrease in velocity of an object caused by friction, air resistance, or other types of resistance. To calculate it, you need to know the object's mass, initial velocity, final velocity, and time taken to decelerate. Common examples include a car slowing down, a ball rolling to a stop, and a skydiver's descent. Factors that affect deceleration due to resistance include surface area, speed, medium density, and object shape. It differs from acceleration as it is the opposite and caused by a force in the opposite direction of motion.
  • #1
cpalm
1
0
I have a rocket with a top velocity of 14.16 m/s when the engine stops.

How do i calculate its deceleration based on air resistance and gravity if it is flying at approximatly 45 degress?
 
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  • #2
There is no easy way to deal with air resistance. It is ignored in most courses.
Also, we usually simplify matters by saying the engine burns for so small a time it is effectively zero.

So, it is just another baseball problem. Do the horizontal and vertical parts separately.
 
  • #3


To calculate deceleration due to resistance, we first need to understand the factors that contribute to resistance. In this case, we have air resistance and gravity acting on the rocket. Air resistance, also known as drag, is the force that opposes the motion of the rocket as it moves through the air. Gravity, on the other hand, is a constant force that pulls the rocket towards the ground.

To calculate deceleration, we can use the equation F = ma, where F is the total force acting on the rocket, m is the mass of the rocket, and a is the resulting acceleration. In this case, we can break down the total force into its components: the force of air resistance (Fdrag) and the force of gravity (Fg).

F = Fdrag + Fg

Since we know the top velocity of the rocket (14.16 m/s), we can use this information to calculate the force of air resistance using the equation Fdrag = 0.5 * ρ * A * v^2, where ρ is the density of air, A is the cross-sectional area of the rocket, and v is the velocity of the rocket.

Next, we need to calculate the force of gravity using the equation Fg = mg, where m is the mass of the rocket and g is the acceleration due to gravity (9.8 m/s^2).

Now, we can plug in these values into our original equation to calculate the total force acting on the rocket:

F = 0.5 * ρ * A * v^2 + mg

To calculate the resulting deceleration, we can rearrange the equation to solve for a:

a = (0.5 * ρ * A * v^2 + mg)/m

Since the rocket is flying at approximately 45 degrees, we can also take into account the component of gravity and air resistance acting in the vertical direction. This can be done by using trigonometric functions to calculate the vertical and horizontal components of these forces.

In summary, to calculate deceleration due to resistance, we need to consider the forces of air resistance and gravity acting on the rocket and use the equation F = ma to calculate the resulting acceleration. We can also take into account the angle of flight to calculate the vertical and horizontal components of these forces.
 

Related to How do you calculate deceleration due to resistance?

1. What is deceleration due to resistance?

Deceleration due to resistance is the decrease in velocity or speed of an object due to the forces of friction, air resistance, or any other type of resistance acting upon it.

2. How do you calculate deceleration due to resistance?

To calculate deceleration due to resistance, you need to know the mass of the object, the initial velocity, and the final velocity. Then, you can use the formula a = (vf - vi) / t, where a is the deceleration, vf is the final velocity, vi is the initial velocity, and t is the time taken to decelerate.

3. What are some common examples of deceleration due to resistance?

Some common examples of deceleration due to resistance include a car slowing down due to air resistance and friction between the tires and the road, a ball rolling to a stop due to the friction between the ball and the ground, and a skydiver slowing down as they fall due to air resistance.

4. What factors can affect deceleration due to resistance?

The most significant factor that affects deceleration due to resistance is the surface area of the object. The larger the surface area, the more air resistance or friction it will experience, resulting in a higher deceleration. Other factors that can affect deceleration due to resistance include the speed of the object, the density of the medium, and the shape of the object.

5. How does deceleration due to resistance differ from acceleration?

Deceleration due to resistance is the opposite of acceleration. While acceleration is the increase in velocity, deceleration is the decrease in velocity. Acceleration is caused by a force acting in the same direction as the object's motion, while deceleration is caused by a force acting in the opposite direction of the object's motion.

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