falcon306

A 2000 {\rm kg} car traveling at a speed of 13 {\rm m/s} skids to a halt on wet concrete where mu_k = 0.50. How long are the skid marks? I tried doing this many times and each answer is wrong. Can someone help?

A 1300 kg car is traveling along a straight road at 20 m/s. Two seconds later its speed is 24 m/s. What is the magnitude of the net force acting on the car during this time? I don't know what equation to use, and I keep getting stuck

A loudspeaker of mass 24.0 {\rm kg} is suspended a distance of h = 2.20 {\rm m} below the ceiling by two cables that make equal angles with the ceiling. Each cable has a length of l = 3.30 {\rm m}. What is the tension T in each of the cables? Use 9.80 {\r...

How much force does an 88 kg astronaut exert on his chair while sitting at rest on the launch pad? Answer: 860N Now the question: How much force does the astronaut exert on his chair while accelerating straight up at 14 m/s^2? What do you do first, how do...

The centers of a 15 kg lead ball and a 140 g lead ball are separated by 8.0 cm. What gravitational force does each exert on the other? Answer: 2.2×10^−8 N Now: What is the ratio of this gravitational force to the weight of the 140 g ball? I don't know how...

An object's moment of inertia is 2.5 kgm^2. Its angular velocity is increasing at the rate of 3.0 rad/s^2. What is the torque on the object? In N*m units

Flywheels are large, massive wheels used to store energy. They can be spun up slowly, then the wheel's energy can be released quickly to accomplish a task that demands high power. An industrial flywheel has a 1.5 m diameter and a mass of 250 kg. Its maxim...

A spring exerts a 17 N force after being stretched by 3.0 cm from its equilibrium length. By how much will the spring force increase if the spring is stretched from 5.0 cm away from equilibrium to 6.0 rm cm from equilibrium? I don't know how to approach t...

A 3.0-m-long rigid beam with a mass 130 kg is supported at each end. An 90 kg student stands 2.0 m from support 1. (beam 1 is to the left, and beam 2 is on the right.) How much upward force does support 1 exert on the beam? How much upward force does supp...

A man standing on very slick ice fires a rifle horizontally. The mass of the man together with the rifle is 70 kg, and the mass of the bullet is 10g. Q:If the bullet leaves the muzzle at a speed of 500 m/s, what is the final speed of the man? I don't know...

A 1.1 kg book is lying on a 0.77 m -high table. You pick it up and place it on a bookshelf 2.3 m above the floor. 1. How much work does gravity do on the book? 2. How much work does your hand do on the book? How do you find work?

A car is traveling at 14 m/s. How fast would the car need to go to double its kinetic energy? By what factor does the car's kinetic energy increase if its speed is doubled to 28 m/s? We only get 3 chances and I'm on my last one before I get the question w...

Marissa drags a 15 kg duffel bag 18 m across the gym floor. If the coefficient of kinetic friction between the floor and bag is 0.15, how much thermal energy does Marissa create? It says I'm look for deltaE_Th. I don't know what that means or how to figur...

Thank you very much!

Thank you!

I'm not sure how to solve for k though.

Awesome thanks a lot!

Never mind I got it!

That really helped thank you very much