Need help with projectile/friction problem.

  • Thread starter Shipman515
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In summary, the conversation discusses a popular pastime of pushing an object closest to the edge of a table without it falling off. In this scenario, a 100 g object is pushed and released 3.00 m from the table edge. However, it is pushed too hard and slides off the edge, falling 1.30 m to the floor and landing 25.0 cm from the table edge. With a coefficient of kinetic friction of 0.500, the conversation then explores how to calculate the object's initial speed when it was released. Suggestions are given to use the equations for kinetic energy and gravitational potential energy, as well as the distance and time traveled by the object. The helpers also remind the OP to keep in mind
  • #1
Shipman515
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A popular pastime is to see who can push an object closest to the edge of a table without its going off. You push the 100 g object and release it 3.00 m from the table edge. Unfortunately, you push a little too hard. The object slides across, sails off the edge, falls 1.30 m to the floor, and lands 25.0 cm from the edge of the table.

If the coefficient of kinetic friction is 0.500, what was the object's speed as you released it?

I've tried a lot of different things, suggestions?
 
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  • #2
I don't know if this will help but have u tried

kinetic energy = gravitational potential energy

1mv^2/2 = mgh
 
  • #3
t = time to fall
y = vertical distance
g = acceleration (9.8m/s^2)
x = distance traveled off table
v1 = initial speed
v2 = speed as object leaves table (x component)


y = (1/2)*g*t^2 therefore t = (2*y/g)^(1/2)
x = v2*t therefore x = v2*(2*y/g)^(1/2)

Maybe someone can finish this for you. I apologize my laptop is dying:(
 
  • #4
try to figure out the velocity when it leaves the table and starts falling. If you find it, you can find its kinetic energy at the instant. Since there is friction on the table, the kinetic friction caused the mass to be slowed down from the initial velocity it took off from. how much did it slow down, or how much energy did it lose to friction? If you know that than, you can trace back and find the initial velocity.
 
Last edited:
  • #5
Please keep in mind that the rules of this forum are that the "helpers" should only guide the OP, not do or work out the solution.

Zz.
 
  • #6
Got it. Thanks ya'll. really helped.
 

1. What is a projectile?

A projectile is any object that is thrown, shot, or launched into the air and moves along a curved path due to the influence of gravity.

2. How do you calculate the trajectory of a projectile?

The trajectory of a projectile can be calculated using the equations of motion, which take into account the initial velocity, acceleration due to gravity, and time of flight. It can also be calculated using vector components and the principles of trigonometry.

3. What is the role of friction in projectile motion?

Friction is a force that opposes the motion of an object and can have a significant impact on the trajectory of a projectile. It can cause the projectile to slow down and deviate from its intended path.

4. How can friction be minimized in projectile motion?

Friction can be minimized in projectile motion by reducing the contact between the projectile and the surface it is moving on. This can be achieved by using a smoother surface or adding lubrication.

5. What real-life applications involve projectile motion?

Projectile motion is used in various real-life applications, such as sports like baseball, basketball, and golf. It is also used in military and defense systems, space exploration, and transportation systems such as rockets and missiles.

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