# Force that's acting on the truck

• zerogoal
In summary: Nground and Nb pointing upwards, length of Nground longer than Nb.Fk and Froad pointing right, length of Froad longer than Fk.Wt pointing down.This is incorrect. The forces in the y direction should not add to zero. They should cancel each other out. The correct diagram would be: Nground and Nb pointing upwards, length of Nground longer than Nb.Fk and Froad pointing right, Froad has length Fk and Fk has length zero.Wt pointing down.
zerogoal

## Homework Statement

A large box containing your new computer sits on the bed of your pickup truck. You are stopped at a red light. The light turns green and you stomp on the gas and the truck accelerates. To your horror, the box starts to slide toward the back of the truck. (Assume that the truck is accelerating to the right.)

Draw clearly labeled free-body diagram for the truck. (The bed of the truck is not frictionless.)
Draw the force vectors with their tails at the dot. The orientation of your vectors will be graded. The exact length of your vectors will not be graded but the relative length of one to the other will be graded.

## Homework Equations

Nground: normal force
Nb: reaction to the normal force on the box from the truck
Froad: Reaction force to tires' backward push
Fk: box friction force on the truck bed
Wt: weight of truck

## The Attempt at a Solution

1st attempt:

Nground and Nb pointing upwards, length of Nground longer than Nb.
Fk pointing right.
Wt pointing down.
*length of my Nground and Wt arrows are equal

2nd attempt:

Nground and Nb pointing upwards, length of Nground longer than Nb.
Wt pointing down.
*length of my Nground and Wt arrows are equalHowever i can't seem to get the correct free body diagram for this. Can anyone help?
Should i change the Nb of my 2nd attempt to acting downwards instead of acting upwards?

Last edited:
zerogoal said:
Should i change the Nb of my 2nd attempt to acting downwards instead of acting upwards?
Yes, that will help. The direction of Nb can be determined from Newton 3, by first examining the forces on the crate. Check that friction direction also in the same manner...is it correct?

How long should the length of my Nb be?

zerogoal said:
How long should the length of my Nb be?
Just the way you said it, Ng longer than Nb. Do you understand why? And don't forget to rexamine the direction of the friction force and why it is in that direction. Just guessing won't do you any good. You have another error as well.

I just figured this one out! Don't forget that the forces in the y direction have to add to zero...might need to change the length of a vector to make that true...

## What is force?

Force is a physical quantity that can change the state of motion or shape of an object. It is a vector quantity, meaning it has both magnitude and direction.

## What is the difference between force and net force?

Force refers to any push or pull that is exerted on an object, while net force is the combination of all the forces acting on an object. Net force determines the overall motion of an object.

## What is the formula for calculating force?

The formula for calculating force is F = m x a, where F is force, m is mass, and a is acceleration. This is known as Newton's second law of motion.

## What are some examples of forces acting on a truck?

Some examples of forces acting on a truck include gravity, friction, air resistance, and the force of the engine pushing the truck forward.

## How does the force acting on a truck affect its motion?

The force acting on a truck determines its acceleration and, ultimately, its motion. If the force pushing the truck forward is greater than the forces acting against it, such as friction and air resistance, the truck will accelerate and move in the direction of the net force.

• Introductory Physics Homework Help
Replies
24
Views
1K
• Introductory Physics Homework Help
Replies
10
Views
4K
• Introductory Physics Homework Help
Replies
4
Views
16K
• Introductory Physics Homework Help
Replies
1
Views
2K
• Introductory Physics Homework Help
Replies
2
Views
11K
• Introductory Physics Homework Help
Replies
1
Views
2K
• Introductory Physics Homework Help
Replies
5
Views
4K
• Introductory Physics Homework Help
Replies
1
Views
13K
• Introductory Physics Homework Help
Replies
3
Views
4K
• Introductory Physics Homework Help
Replies
6
Views
7K