A block of mass m is compressed against a spring (spring constant kk) on a horizontal frictionless surface. The block is then re
leased and subsequently falls from a high ground of height hh. The maximum compression of the spring before the block was released is \Delta xΔx. The velocity of the block after release is v_1v1. The velocity of the block when it hits the ground is v_2v2. A.If the block started with a compression of \frac{1}{2}\Delta x21Δx, the block velocity after leaving would be \frac{1}{2}v21v.
B.The mechanical energy of this system is not conserved.
C.If height h is changed to h=2hh=2h, then the velocity of the block v_2v2 will be changed into v_2=2vv2=2v.
D.If the block started with a compression of 3\Delta x3Δx, the block’s velocity after leaving would be 6v6v.
E.None of the above statements are true.
A futuristic design for a car is to have a large solid disk-shaped flywheel within the car storing kinetic energy. The uniform flywheel has mass 370 kg with a radius of 0.500 m and can rotate up to 320 rev/s. Assuming all of this stored kinetic energy could be transferred to the linear velocity of the 3500-kg car, find the maximum attainable speed of the car.
In a chemical reaction, the substances that undergo change are called reactants. The new substances formed as a result of that change are called products.
