Solving Equations of Motion for Speed Traps, Sleds & Snakes

In summary: That will be the best way to practice kinematics.In summary, the conversation discusses the acceleration and speed of a snake's head as it strikes a victim, the acceleration and distance traveled of a rocket in deep space, the acceleration experienced by a person on a rocket-propelled sled, the acceleration and time taken by a high-speed train between speed traps, and the acceleration and required speed for a rocket sled to travel a certain distance. The kinematics equations can be used to solve for the variables in each problem.
  • #1
deltangh
2
0
The head of a snake can accelerate at 50 m/s2when it strikes. The snake’s head starts from rest and
accelerates constantly until it strikes a victim that is 0.5 m away.
a) How fast is the snake’s head moving when it hits the victim?
b) How long does it take the snake’s head to get to the victim?


Q 2. A rocket coasting at 20,000 m/s in deep space fires its engines so that it accelerates at 20 m/s2.
a) How long will it have to keep accelerating to get to a speed of 300,000 m/s?
b) How far will it travel while it is accelerating?


Q 3. A world land speed record was set by Mr. John when he rode a rocket-propelled sled at 283.3 m/s. The
sled was brought to a stop in 1.4s. What acceleration did Mr. John experience?


Q 4. A high-speed train starts from rest and moves with constant acceleration. As it passes a speed trap, a
bored police officer uses a radar gun to measure the train’s speed as 30 m/s. At another speed trap, 160 m
further down the track, another officer measures the train’s speed as 50 m/s.
a) How quickly was the train accelerating?
b) How long did it take to travel the 160 m between speed traps?


Q 5. A boy is inspired by Mr. John’s example to take up rocket sledding. He builds a track so he can get a
modern rocket sled to go from rest up to 445 m/s. If his track is only 225 m long, how quickly will boy (and
sled) have to accelerate to reach the target speed by the end of the track?
 
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  • #2
For number one, refer to the definition of acceleration. What is it equal to? Play with the variables to solve for the variable you are seeking (which is the speed in this case). The same applies to the other 4.

edit: Think of the kinematics equations and how you can apply them to the problems.
 
  • #3
Thanks, i need the answer keys of this questions!
 
  • #4
deltangh said:
Thanks, i need the answer keys of this questions!

Sorry, but here we don't give out answers. You're expected to find the answer yourself with help from us if it is (and apparently it is) required. What don't you understand in the problems? Can you write the 5 kinematics equations (not the definitions of position, velocity, and acceleration)? If not, then you should check the textbook you have or review your notes.
 
  • #5
The best way to practice is to write down the 4 equations on a paper and write the variables given by the question.Then search for the relevant equation which fits for all the variables(You may have to find some variables yourself (eg:Speed when distance and time is given))
 

FAQ: Solving Equations of Motion for Speed Traps, Sleds & Snakes

1) How do you solve equations of motion for speed traps?

To solve equations of motion for speed traps, you need to first define the variables involved, such as initial velocity, final velocity, acceleration, and time. Then, plug these values into the appropriate equation, such as v = u + at, where v is final velocity, u is initial velocity, a is acceleration, and t is time. Solving for the desired variable will give you the answer.

2) What is the importance of solving equations of motion for speed traps?

Solving equations of motion for speed traps is important because it allows us to accurately determine the speed of an object at a specific point in time. This information is crucial in various fields, such as law enforcement, sports, and engineering, to name a few.

3) Can equations of motion be used for objects other than speed traps?

Yes, equations of motion can be used for any object undergoing motion. They are commonly used in physics to describe the motion of objects such as cars, projectiles, and even celestial bodies like planets and stars.

4) How do you solve equations of motion for sleds on an inclined plane?

To solve equations of motion for sleds on an inclined plane, you need to take into account the angle of the slope. This will affect the acceleration of the sled, which can be calculated using the formula a = g*sin(θ), where g is the acceleration due to gravity and θ is the angle of the slope. The rest of the steps are similar to solving equations of motion for speed traps.

5) Can equations of motion be used for living organisms like snakes?

Yes, equations of motion can be used for living organisms like snakes. However, they may not be as accurate for living organisms as they are for inanimate objects, as living organisms can exhibit complex and unpredictable movements. In such cases, other factors such as muscle forces and biomechanics may also need to be considered in the equations.

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