Solving Physics Problems: A & B

In summary, we have two questions. For the first question, we need to find the work done on a plane landing on an aircraft carrier and the force exerted on the plane by the arresting cables. For the second question, we need to find the average mechanical power output of a car's engine and the volume of gasoline consumed. Both questions require using the concepts of work and energy.
  • #1
bubba640
4
0
PLEASE HELP I'M CLUELESS ON THESE PROBLEMS

FOR THIS QUESTION I FOUND B BUT I HAVE NO IDEA ON HOW TO FIND A.

A plane weighing 220 kN (25 tons) lands on an aircraft carrier. The plane is moving horizontally at 62 m/s (139 mi/h) when its tailhook grabs hold of the arresting cables. The cables bring the plane to a stop in a distance of 88 m.
(a) How much work is done on the plane by the arresting cables?
MJ

(b) What is the force (assumed constant) exerted on the plane by the cables?
kN opposite the plane's direction of motion
(Note: Both answers will be underestimates, since the plane lands with the engines full throttle forward; in case the tailhook fails to grab hold of the cables, the pilot must be ready for immediate takeoff.)

AND FOR THIS QUESTION I FOUND A BUT HAVE NO IDEA ON HOW TO FIND B.


A car with mass of 1000.0 kg accelerates from 0 m/s to 40.0 m/s in 12.0 s. Ignore air resistance. The engine has a 23% efficiency, which means that 23% of the thermal energy released by the burning gasoline is converted into mechanical energy.
(a) What is the average mechanical power output of the engine?
kW
(b) What volume of gasoline is consumed? Assume that the burning of 1.0 L of gasoline releases 47 MJ of thermal energy.
L
 
Physics news on Phys.org
  • #3


You've already done (a)? That should have been easy: the airplanes kinetic energy is reduced to 0 by the work done. For (b), now use that: Work= Force times distance. You know the work done, divide by the distance it takes to stop the airplane.

For the second problem, the car's kinetic energy has gone from 0 to (1/2) mv2. How much work must have been done? "Power" is work divided by time. That total energy is 23% of the actual energy produced by the gasoline and you are told that "burning of 1.0 L of gasoline releases 47 MJ of energy".
 
  • #4


OKAY SO FOR THE FIRST QUESTION
WORK = KINETIC ENERGY

SOOOO
Average impact force x distance traveled = change in kinetic energy

f=MA
F=22448.9 KG* 490.3=11006695.67

CHANGE IN KINETIC ENERGY= 11006695.67* 88= 968589218.96

IS THIS RIGHT??
 

What are the steps involved in solving a physics problem?

The steps involved in solving a physics problem are: understanding the problem, identifying the given information and what needs to be solved, choosing the appropriate equations and concepts, solving the equations, and checking the answer for accuracy.

How do I know which equations to use to solve a physics problem?

You can determine which equations to use by identifying the known quantities and what needs to be solved for. Look for equations that contain those variables. Also, consider the concepts and principles involved in the problem, as they can also guide you to the appropriate equations.

What should I do if I get stuck on a physics problem?

If you get stuck on a physics problem, take a step back and review the information and equations you have gathered. Consider approaching the problem from a different perspective or breaking it down into smaller parts. You can also consult with a classmate or teacher for guidance.

How important is it to show all of my work when solving a physics problem?

Showing your work is crucial in physics problem solving. It not only helps you keep track of your thought process and calculations, but it also allows others to understand and verify your solution. Additionally, partial credit may be given for showing your work, even if the final answer is incorrect.

What strategies can I use to improve my problem-solving skills in physics?

To improve your problem-solving skills in physics, it is important to practice regularly. Start with simple problems and gradually move on to more complex ones. Break down the problem into smaller parts and focus on one step at a time. Additionally, seek help from resources such as textbooks, online tutorials, and your teacher or classmates.

Similar threads

  • Introductory Physics Homework Help
Replies
2
Views
2K
  • Introductory Physics Homework Help
2
Replies
41
Views
4K
  • Introductory Physics Homework Help
Replies
3
Views
4K
  • Introductory Physics Homework Help
Replies
4
Views
1K
  • Introductory Physics Homework Help
Replies
6
Views
15K
  • Introductory Physics Homework Help
Replies
12
Views
2K
  • Introductory Physics Homework Help
Replies
2
Views
2K
  • Introductory Physics Homework Help
Replies
9
Views
6K
  • Introductory Physics Homework Help
Replies
1
Views
1K
  • Introductory Physics Homework Help
Replies
10
Views
3K
Back
Top