Achair of weight 90.0 n lies atop a horizontal floor; the floor is not frictionless. you push on the chair with a force of f = 38.0 n directed at an angle of 42.0 degrees below the horizontal and the chair slides along the floor.
using newton's laws, calculate n, the magnitude of the normal force that the floor exerts on the chair.

Give one example to show that when substances are mixed, it may result in a chemical or a physical change depending on the conditions.

Consider a uniformly charged ring in the xy plane, centered at the origin. the ring has radius a and positive charge qdistributed evenly along its circumference. a)what is the direction of the electric field at any point on the z axis? . b)what is the magnitude of the electric field along the positive z axis? use k in your answer, where k=14πϵ0. d)the ball will oscillate along the z axis between z=d and z=−d in simple harmonic motion. what will be the angular frequency ω of these oscillations? use the approximation d≪a to simplify your calculation; that is, assume that d2+a2≈a2. express your answer in terms of given charges, dimensions, and constants

Aforce of 8,480 n is applied to a cart to accelerate it at a rate of 26.5 m/s2. what is the mass of the cart?