john is pushing a wheelbarrow filled with sand on a building site the total mass of the wheelbarrow and it's content is 30kg when he applies a force of 20N the wheelbarrow moves forward at a constant speed, what is the magnitude of the friction between the wheel and the ground and the foreman shouts at john to hurry up and he increases his pushing force of 50N calculate the wheelbarrow acceleration​

Consider a hydrogen atom in the ground state. what is the energy of its electron? =e= jj now consider an excited‑state hydrogen atom. what is the energy of the electron in the =5n=5 level? =e5= j

What is the orbital period of a spacecraft in a low orbit near the surface of mars? the radius of mars is 3.4×106m.

10 points! will mark brainiest! in a heat engine if 1,000 j of heat enters the system and the piston does 500 j of work, what is the final internal energy of the system if the initial energy was 2,000 j 1: write the equation 2: list out your known variables 3: plug the numbers into the equations 4: solve 5: write your solution statement that includes initial energy and final energy added you so much!