Physical Science This test covers what you learned in Unit 1 including: ◦ ◦ ◦ ◦ Contact and Non-Contact Forces How to measure motion (speed and velocity) Balanced and unbalanced forces Newton’s Laws of Motion Quiz yourself by going through the slides. To check your answer or get to the next question, click on the balloon car. Good Luck! The amount of matter in an object is called? a. Weight b. Mass c. stuff What do you call a force that gravity exerts on an object’s mass? a. b. c. Magnetism Friction Weight What is a force that acts to pull pairs of objects together? a. b. c. Gravity Magnetism electricity The tendency for an object to stay in motion or to stay at rest is called? a. b. c. acceleration friction inertia Which picture shows magnetic attraction? a. b. Click on the picture that shows magnetic repulsion. Is magnetism a contact or non-contact force? Pushes and pulls that result from direct touching of objects are called? a. contact forces b. non-contact forces A push, pull or turn is called? a. a force b. friction c. a new dance move What is the formula for speed and what do you call speed in a certain direction? a. b. c. Time ÷ distance / Distance ÷ time / Distance ÷ time / velocity newtons velocity Friction caused by molecules in the air is called? a. b. c. sliding friction rolling friction air resistance A force that resists movement of one surface past another surface is called? a. b. c. gravity friction magnetism What do you call a change in velocity? a. b. c. speed acceleration melocity The greater the mass, the greater the force needed to accelerate the object. This is Newton’s a. b. c. First Law Second Law Third Law An object in motion stays in motion, an object at rest stays at rest unless acted upon by an outside force. This is Newton’s a. First Law b. Second Law c. Third Law For every action, there is an opposite and equal reaction. This is Newton’s a. b. c. First Law Second Law Third Law Forces are measured in….. a. b. c. Meters Grams Newtons B. Mass C. Weight A. gravity B. Opposite poles attract inertia This is Newton’s First Law of Motion C. Oops! Wrong Answer Try again! You got it! Like poles repel each other. Non-contact Contact Forces Example: A force (of course!) c. Distance ÷time = speed velocity is speed in a certain direction Air resistance Important uses of friction: a. b. c. Walking – you couldn’t walk without friction between your shoes and the ground. Writing – you couldn’t hold a pencil without friction. Driving a car – you couldn’t move without friction between the tires and the road. Problems from friction: a. b. c. Makes movement difficult. Wastes energy – in a vehicle - excess friction means extra fuel is needed. Wears things out – machines with moving parts can wear out due to friction. Lubrication such as oil can reduce friction. Newton’s Second Law of Motion Force = mass x acceleration Newton’s First Law of Motion Also known as the Law of Inertia Newton’s Third Law of Motion Newtons Acceleration