Ice Sled Powered by Rocket Engine: Find t1, t2, v & Final Position

In summary, the sled moves from rest to a final position of 15750 ft in 90 seconds and has a velocity of 38 ft/s2.
  • #1
funwithphysics
1
0
An ice sled powered by a rocket engine starts from rest on a large frozen lake and accelerates at +38 ft/s2. After some time t1, the rocket engine is shut down and the sled moves with constant velocity v for a time t2. Assume the total distance traveled by the sled is 15750 ft and the total time is 90 s.
(a) Find the times t1 and t2.
t1
t2
(b) Find the velocity v.
ft/s
At the 15750 ft mark, the sled begins to accelerate at -21 ft/s2.
(c) What is the final position of the sled when it comes to rest?
ft
(d) What is the duration of the entire trip?

Please just show me how to do this. My entire weekend has consisted of me holed up in my basement doing physics. This is my last problem and I just want to feel happy and alive again :(
s
 
Physics news on Phys.org
  • #2


Welcome to PF funwithphysics!

funwithphysics said:
An ice sled powered by a rocket engine starts from rest on a large frozen lake and accelerates at +38 ft/s2. After some time t1, the rocket engine is shut down and the sled moves with constant velocity v for a time t2. Assume the total distance traveled by the sled is 15750 ft and the total time is 90 s.
(a) Find the times t1 and t2.
t1
t2
(b) Find the velocity v.
ft/s
At the 15750 ft mark, the sled begins to accelerate at -21 ft/s2.
(c) What is the final position of the sled when it comes to rest?
ft
(d) What is the duration of the entire trip?

Please just show me how to do this. My entire weekend has consisted of me holed up in my basement doing physics. This is my last problem and I just want to feel happy and alive again :(
s

No, please read our site rules. We won't do your homework for you here. Instead, let's go through this step by step. Start with the first phase of the motion, between t = 0 and t = t1. This is the constant acceleration portion of the trip. Write down an expression for the distance vs. time during this phase.

Next, write an expression for the distance vs. time during the second portion, between t = t1 and t = t2. This is a constant velocity portion of the trip, and you know what v is in terms of 'a' and t1.

You know that the two distances have to add up to 15,750 ft, and that the two times have to add up to 90 s.

That gives you two equations, and two unknowns. So you can solve for both of them.
 
  • #3


OK . Your last line was funny.

From your problem
Eq 1 : t1 + t2 = 90 seconds

also, distance traveled during acceleration + distance at constant velocity v is 15750 feet
Eq 2: d1 + d2 = 15750 feet

acceleration,
Eq 3: a1 = 38 ft/s^2
Eq 4: a2 = 0



From an equation of linear motion,
x = x0 + 1/2 vt
x = x0 + v0 t + 1/2 a t^2
v = v0 + at
v^2 = v0^2 + 2 a d

Can you think how to manipulate those equations to solve for t1, t2 and v in your problem?
 

1. What is an ice sled powered by a rocket engine?

An ice sled powered by a rocket engine is a type of vehicle that uses a rocket engine to propel itself over a surface covered in ice. It combines the speed and power of a rocket with the slick surface of ice to create a unique and exciting mode of transportation.

2. How do you determine t1, t2, v, and final position for an ice sled powered by a rocket engine?

To determine t1, t2, v, and final position for an ice sled powered by a rocket engine, you would need to know the initial velocity of the sled, the acceleration due to the rocket engine, and the distance traveled over a given time period. Then, you can use equations of motion to calculate the values.

3. What factors can affect the performance of an ice sled powered by a rocket engine?

There are several factors that can affect the performance of an ice sled powered by a rocket engine. These include the type and power of the rocket engine, the weight and design of the sled, the condition of the ice surface, and external factors such as wind and friction.

4. Is an ice sled powered by a rocket engine safe?

As with any vehicle, safety precautions should be taken when operating an ice sled powered by a rocket engine. It is important to follow proper instructions and wear appropriate safety gear such as a helmet and protective clothing. Additionally, the sled should be tested and operated in a controlled environment to minimize risks.

5. Are there any alternative ways to power an ice sled besides a rocket engine?

There are alternative ways to power an ice sled, such as using a motor or propeller. However, a rocket engine may provide the most powerful and efficient means of propulsion for an ice sled, making it a popular choice among enthusiasts and professional racers.

Similar threads

  • Introductory Physics Homework Help
Replies
23
Views
6K
  • Introductory Physics Homework Help
Replies
11
Views
2K
  • Introductory Physics Homework Help
Replies
4
Views
2K
  • Introductory Physics Homework Help
Replies
4
Views
2K
  • Introductory Physics Homework Help
Replies
1
Views
1K
  • Introductory Physics Homework Help
Replies
18
Views
1K
  • Introductory Physics Homework Help
Replies
3
Views
8K
  • Introductory Physics Homework Help
Replies
2
Views
2K
Replies
8
Views
5K
  • Introductory Physics Homework Help
Replies
2
Views
1K
Back
Top