Solving Physics: Chris the Inventive - Acceleration & Force

  • Thread starter bahamut1111
  • Start date
In summary, an inventive child named Chris wants to reach an apple in a tree without climbing the tree. To do so, Chris sits in a chair connected to a rope passing over a frictionless pulley. By pulling on the loose end of the rope with a force of 272.5 N, measured by a spring scale, Chris is able to lift their true weight of 464 N and the chair's weight of 67 N. Using the acceleration of gravity g = 9.8 m/s2, the acceleration of the system is found to be 0.258 m/s2. The magnitude of the force Chris exerts on the chair can be calculated using F=ma, but it was marked incorrect when attempted in both
  • #1
bahamut1111
6
0
An inventive child named Chris wants to reach
an apple in a tree without climbing the tree.
Sitting in a chair connected to a rope that
passes over a frictionless pulley, Chris pulls
on the loose end of the rope with such a force
that the spring scale reads 272.5 N. Chris’s
true weight is 464 N, and the chair weighs
67 N.
The acceleration of gravity is g = 9.8 m/s2 .
A. Find the magnitude of the acceleration of
the system.
Answer in units of m/s2.

B.
Find the magnitude of the force Chris exerts
on the chair.
Answer in units of N.



i got the acelleration and it was marked correct (0.258380414312617702)

but when i look for the force which i used f=ma... it was marked wrong... i tried first in N than in kg and still nothing...
 
Physics news on Phys.org
  • #2
Chair is going up with an acceleration a. Weight of Chris acts in down ward direction. So net reaction on the chair is F = m(a+g)
 
  • #3
ok would i use the mass of the chair only or include the kids too?
 

FAQ: Solving Physics: Chris the Inventive - Acceleration & Force

1. What is acceleration?

Acceleration is the rate of change of an object's velocity. It is a vector quantity, meaning it has both magnitude and direction. In simpler terms, acceleration is the measure of how fast an object's velocity is changing over time.

2. How is acceleration calculated?

Acceleration can be calculated by dividing the change in an object's velocity by the change in time. The formula for acceleration is a = (vf - vi) / t, where a is acceleration, vf is the final velocity, vi is the initial velocity, and t is time.

3. What is the relationship between acceleration and force?

According to Newton's Second Law of Motion, the acceleration of an object is directly proportional to the net force acting on the object and inversely proportional to the object's mass. This means that if the force acting on an object increases, its acceleration will also increase, and if the mass of the object increases, its acceleration will decrease.

4. How does Chris use acceleration and force in his inventions?

Chris, being an inventive scientist, understands the principles of acceleration and force and uses them to create various machines and gadgets. For example, he can use the concept of acceleration to design a rocket that can travel at high speeds, or he can use the principles of force to develop a pulley system that makes lifting heavy objects easier.

5. Can acceleration and force be negative?

Yes, acceleration and force can be negative. Negative acceleration, also known as deceleration, occurs when an object's velocity decreases over time. Negative force, on the other hand, is a force that acts in the opposite direction of an object's motion. For example, when a car is slowing down, it experiences negative acceleration, and when a car is pushed in the opposite direction of its motion, it experiences negative force.

Similar threads

How Does Nick's Acceleration Change When His Friend Pulls the Rope?
Replies
6
Views
3K
Solving Forces Confusion: Finding Chris's Force on Chair
Replies
5
Views
4K
Summing forces: finding acceleration and F_n
Replies
5
Views
29K
How Does a Pulley System Help Rescue a Cat from a Tree?
Replies
9
Views
2K
Calculating Net Force on a Wheel: Magnitude and Direction | 0.350 m Radius
Replies
4
Views
1K
Show that the acceleration of the system is upward
Replies
8
Views
7K
Forces acting on a box-pulley system in an elevator?
Replies
33
Views
7K
How Do You Calculate Net Force and Coefficient of Friction in Physics Problems?
Replies
15
Views
3K
Lowering a climber with the belay rope routed through a pulley at an angle
Replies
12
Views
2K
Newton's Third Law: Acceleration of box and worker
Replies
2
Views
4K

Hot Threads

Recent Insights

Back
Top