A mass of m = 3kg is pressed against a spring of spring constant k = 2N/m with a force of 1N. The force is removed and spring pushes the mass away. The mass slides d₁ = 1m on a frictionless surface and then d₂ = 0.1m on a rough (friction) surface where it comes to rest. Answer the following questions. Space for a picture: (a) What is the Potential Energy stored in the spring?

When a spring is compressed by 2.0 cm, its spring potential energy is 16.9 J. What will its spring potential energy be if it is stretched by 4.0 cm, in Joule? Your answer needs to have 2 significant figures, including the negative sign in your answer if needed. Do not include the positive sign if the answer is positive. No unit is needed in your answer, it is already given in the question statement.

Two 37.0-lbm twins are playing in their backyard. One toddler is running full speed at 5.5 mph and his path will take him directly into a brick wall. His sister has climbed a 3.5-ft ladder and is perched precariously atop it. Calculate the kinetic and potential energies of the two twins with respect to their stationary destinations (the wall and the ground). Boy Girl i KE (lbf.ft) PE (lbf.ft) If potential energy is completely converted to kinetic energy during the girl's fall, how fast will she be travelling upon impact? mph

On a playground slide, a child has potential energy PE = 450.0 J at the top of the slide. Thechild’s mass is 25.0 kg. (For simplicity, take the value of g to be 10.0 m/s2 in this problem.) When the child slides down to the bottom of the slide, her KE = 300.0 J. a) What was the height of the slide?b) How much was the work done by friction?c) How fast was the child moving when she reached the middle of the slide? (Assume that thework done by friction is half of what you get in (b). Note that the PE2 is not zero this time.)

A 50-N crate initially has kinetic energy 10.0 J at the top of a rough incline of 60 degrees.   A constant horizontal force is applied to the crate as it moves down the incline in dynamic equilibrium.    Is the work from the following forces positive, negative or zero?   Explain your reasoning. Normal, Weight, Applied and Friction Is the net work positive, negative or zero?  Explain your reasoning. How do your answers for (a) and (b) change if the crate is displace up the incline instead?

samuel has is observing an object. you please determine the work that is done by F = 5i -2j+0k which is a force that is constant in moving samuel's object in a plane . samuel tells you that the object moves due to the force in a straight line in the plane. the straight line connects the points A(1,2) and the point B(3,7). I already know that the correct answer to this question is zero. but the question I have is WHY is it zero. explain why the work is zero in this senario. Not how you get to the answer zero, but why the answer zero can make sense in this scenario. is the forece perpendicualr to the direction? i am confused please help and i will like.

A 69.0-kg athlete leaps straight up into the air from a trampoline with an initial speed of 8.9 m/s. The goal of this problem is to find the maximum height she attains and her speed at half maximum height. What is the gravitational potential energy associated with the athlete? Write a general equation for energy conservation in this case and solve for the maximum height. Substitute and obtain a numerical answer. Write the general equation for energy conservation and solve for the velocity at half the maximum height. Substitute and obtain a numerical answer

Your answer is partially correct. The figure shows an 7.8 kg stone at rest on a spring. The spring is compressed 9.9 cm by the stone. (a) What is the spring constant? (b) The stone is pushed down an additional 26 cm and released.What is the elastic potential energy of the compressed spring just before that release? (c) What is the change in the gravitational potential energy of the stone-Earth system when the stone moves from the release point to its maximum height? (d) What is that maximum height, measured from the release point? (a) Number 172 Units N/m (b) Number 49.75 Units J (c) Number 79.75 Units (d) Number 64.7 Units cm