Recent content by kchurchi

Homework Statement A comet is traveling towards the earth. The comet has a mass of 4.80E+12 kg and a radius of 385 m. The comet is traveling with a speed of 19 km/s and spinning with a period of 0.12 seconds when its center is a distance 1.88E+7 m away from the center of the earth. The comet...

Thanks mfb!

Homework Statement An atwood machince has a m1 = 4.92-kg block resting on a frictionless horizontal ledge. This block is attached to a string that passes over a pulley, and the other end of the string is attached to a hanging m2 = 2.46-kg block. The pulley is a uniform disk of radius...

The spring constant, k, is equal to the weight force divided by the change in position. k = (m*g)/Δx which we are all given. Once I've found the spring constant, now what do I do? I am confused on how to find x(t=0.7s) when I have an unknown amplitude.

Homework Statement A massless spring is hanging vertically. With no load on the spring, it has a length of 0.29 m. When a mass of 0.33 kg is hung on it, the equilibrium length is 0.92 m. At t=0, the mass (which is at the equilibrium point) is given a velocity of 4.80 m/s downward. At t=0.70...

I am not allowed to have the equations of constant acceleration to solve problems. I must derive all equations myself using calculus. How do I even know that the acceleration is constant?

I would use the SUVAT equations but I need to show I derived them, I can't just pick one unfortunately.

Wouldn't that give me the maximum stopping distance? Because I tried doing that and didn't get the right answer.

Homework Statement A 290-N crate rides without constraints on the horizontal floor of a truck. The coefficient of static friction and the coefficient of kinetic friction between the crate and the truck are 0.32 and 0.16, respectively. If the truck is initially traveling at 18 m/s, what minimal...

Homework Statement You want to know the height of a cliff so you throw a rock off the edge with initial speed v0 = 42 m/s upwards, inclined at an angle θ = 27° with respect to the horizontal. You have a friend that records the time that it takes for the rock to hit the bottom of the canyon...

Homework Statement A hockey puck is sliding across a frozen pond with an initial speed of 7.5 m/s. It comes to rest after sliding a distance of 23.7 m. What is the coefficient of kinetic friction between the puck and the ice? v0x = initial speed = 7.5 m/s vfx = final speed = 0 m/s Δx = x...

Does this link work?

Homework Statement You are designing a missile defense system that will shoot down incoming missiles that pass over a perimeter defense post. The set-up is shown below. An incoming missile passes directly above the defense base. Radar at the base can measure the height, h, and speed, v1, of...

"What if you drop an object? What is its initial velocity? What is its acceleration?" The initial velocity of the object is zero, but it's acceleration is the acceleration due to gravity, which is non-zero. This intuitively makes sense to me, but how does this fit the information that...

Okay so I understand that a) True (acceleration = 0) b) You are right, speed has no components since it is a scalar. But using pythag. theorem to find the speed shows us that the components of velocity are squared, summed, and square rooted to find speed. Again, does my direction argument...