# Middle School Science

Total Flash Cards » 53
Text Size: S | M | L
 equal forces acting in opposite directions balanced forces occurs when an object's velocity decreases negative acceleration sum of all forces acting on an object net force total distance divided by total time average speed name for the slant of a line on a graph slope distance divided by time speed a push or pull exerted on a body or object force distance and direction of an object from its starting point displacement tendency to resist change in motion Inertia measure of how far and object has moved distance speed and direction of motion velocity rate of change of position at a specific point in time Instantaneous speed the rate of change in velocity acceleration compare and contrast: distance and displacement both are links; displacement is direction and distance; distance is how far you have moved compare and contrast: speed and velocity both meters per second: speed is distance and velocity is speed and direction explain the difference between positive and negative acceleration positive is speeding up negative is slowing down how are force and motion related?­- both take unbalanced force to cause motion what property of matter is inertia related to? mass a car travels west for 240 kilometers in 4 hours. What is the car's velocity? 60 kilometers per hour west an object goes from a speed of 9 m/s to a total stop in 3 sec.what is the object's velocity? -3 explain what causes an unrestrained passenger in a car to fly forward when the car stops suddenly inertia the amount of matter in an object mass the net force acting on an object is zero blanced forces the speed of an object and the direction of its motion velocity the sum of all the forces acting on an object net force rate of change of the velocity of an object acceleration a measure of how far an object has moved distance the rate of change in position at a given point in time instantaneous speed the distance and direction an object moves from its starting point displacement the total distance an object travels divided by the time of travel average speed the rate of change of an object's position speed unequal forces pushing in opposite direction unbalanced forces any change over time rate an object that is neither speeding up or slowing down travels at a________. constant speed a graph with distance on a vertical axis and time on a horizontal axis distance-time graph when an object is accelerating, its speed is_______. changing state newton's first law an object at rest will remain at rest until an unbalanced force acts on it if the net force acting on a body is zero, will the velocity be zero? no the velocity is constant, the object will not change its motion will all forces cause an object to accelerate? no only an unbalenced force another name for newton's first law of motion inertia an object slowing down has a_______ acceleration negative the velocity of an object must have both a______ and a _________ speed; direction the equation s=d/t is used to calculate the_____ of an object speed in terms of positive, negative, and zero exceleration, how would you describe the motion of a student moving in a cafeteria lunch line stand still- zero forward- positive backwards- negative explain why the second hands of a clock cannot travels at constant velocities they are changing direction can the velocity of a car change when it's acceleration is constant? explain why or why not yes the direction is always changing a car approaching a red traffic light has a_________ acceleration; when the light turns green, the car's acceleration is ____ negative; positive in the equation s=d/t, d stands for______ distance in the equation used to calculate acceleration, Vi stands for _______ and Vf stands for______ initial;final if the acceleration of a skateboarder is ___, the sakteboarder may be soon coming to a stop negative a net __ is necessary for an object to chanege its motion unbalanced a freight train has more__ than a care, so it has great inertia mass if two people push on an object beween them with equal force but in opposing directions, the net force is __? zero