Chang sees the following formula on a website about Newton's second law.
What does the symbol EF in the formula indicate that
Chang needs to do?
ΣΕ
a =
m
He needs to find the net force acting on the object in a
direction.
He needs to use only forces acting in the direction of
motion.
He needs to combine the horizontal and vertical
forces.
He needs to multiply the horizontal and vertical
forces.

According to the law of conservation of mass, in a chemical reaction the total starting mass of all the reactants equal the total final mass of all the products. true or false?

An incident ray through the focal point of a spherical mirror will: reflect through the center of curvature. reflect back through the focal point. reflect parallel to the principle axis. reflect the same direction as the incident ray.

Thomas his older brothers, who own a junk yard, on the weekends to earn extra money. he likes to them push broken-down cars to the back of the junk yard because it makes him feel strong. last saturday, they pushed three cars with different weights, and he noticed he used different amounts of force for each one. the cars were the following weights: white car: 2,700 kg red car: 1,500 kg blue car: 2,100 kg think about how much force is needed to move each car. which correctly lists the cars in order from the most to least amount of force needed to move them? a) white, blue, red b) blue, red, white c) red, white, blue d) white, red, blue