# Mechanics Velocity Physics Problem

• sarthiyah
In summary, velocity in physics is the measure of an object's displacement over time. It is calculated by dividing an object's displacement by the time it took to cover that distance, using the formula v = d/t. The main difference between speed and velocity is that speed is a scalar quantity while velocity is a vector quantity. Acceleration affects velocity by either increasing or decreasing it, depending on whether it is positive or negative. In mechanics, velocity is a crucial concept used in equations such as Newton's laws of motion to analyze and predict the behavior of objects in motion.
sarthiyah
Homework Statement
Relevant Equations
2. A 500 kg automobile travelling at 30 m/s strikes a 100kg stationary pedestrian. The impact duration is 0.1 s and it slows the automobile by 1m/s.

Calculate:
a. the velocity imparted to the pedestrian
b. the force exerted by the vehicle on the pedestrian.
So, I understand that there are 2 objects, so is the equation we are supposed to use is the elastic collision equation, right? I just need help getting started, thank you.

Delta2
Given: m1= 500kg m2= 100kg V1=30m/s t=0.1s V2= 29m/s? a.) v=?

sarthiyah said:
the equation we are supposed to use is the elastic collision equation, right?
Certainly not. Humans do not bounce well.
What other conservation laws do you know?

berkeman

## 1. What is the definition of velocity in physics?

The velocity of an object is defined as the rate of change of its position with respect to time. It is a vector quantity, meaning it has both magnitude (speed) and direction.

## 2. How is velocity calculated in mechanics?

Velocity is calculated by dividing the change in an object's position by the time taken for that change to occur. This can be represented by the equation v = Δx/Δt, where v is velocity, Δx is change in position, and Δt is change in time.

## 3. What is the difference between speed and velocity?

While speed and velocity are often used interchangeably, they have different definitions in physics. Speed is the rate at which an object is moving, while velocity takes into account both speed and direction. Therefore, two objects can have the same speed but different velocities if they are moving in different directions.

## 4. Can an object have a negative velocity?

Yes, an object can have a negative velocity if it is moving in the opposite direction of a chosen reference point. For example, if a car is moving east and then starts moving west, its velocity would be negative with respect to the east direction.

## 5. How does acceleration affect velocity?

Acceleration is the rate of change of velocity. This means that acceleration can increase, decrease, or change the direction of an object's velocity. For example, if a car is accelerating, its velocity will increase over time. If a car is decelerating, its velocity will decrease over time. And if a car is changing direction, its velocity will also change.

• Introductory Physics Homework Help
Replies
6
Views
929
• Introductory Physics Homework Help
Replies
4
Views
1K
• Introductory Physics Homework Help
Replies
20
Views
942
• Introductory Physics Homework Help
Replies
2
Views
1K
• Introductory Physics Homework Help
Replies
4
Views
428
• Introductory Physics Homework Help
Replies
2
Views
1K
• Introductory Physics Homework Help
Replies
21
Views
1K
• Introductory Physics Homework Help
Replies
6
Views
677
• Introductory Physics Homework Help
Replies
2
Views
1K
• Introductory Physics Homework Help
Replies
17
Views
405