Aprofessor has to haul a cart up a ramp. the ramp has an angle of about 10 degrees and is about 5 meters long. his initial speed at the bottom of the ramp is 4.5 m/s, and the cart has a mass of about 80 kg. how hard does he have to push on the cart so that at the top of the ramp, its speed has not dropped below 3.6 m/s? neglecting friction, what is the magnitude of the minimum force he has to exert on the cart?

Could someone . i have tried to solve myself but my calculation is off

The man of mass m1 and the woman of mass m2 are standing on opposite ends of the platform of mass m0 which moves with negligible friction and is initially at rest with s = 0. the man and woman begin to approach each other. derive an expression for the displacement s of the platform when the two meet in terms of the displacement x1 of the man relative to the platform.

Atriangle with equal sides of length 10 cm has -2.5-nc charged objects at each corner. part a determine the direction of the electrical force exerted on the object at the top corner due to the two objects at the horizontal base of the triangle. determine the direction of the electrical force exerted on the object at the top corner due to the two objects at the horizontal base of the triangle. horizontally rightward vertically downward vertically upward horizontally leftward