True or False Physical science
Write true if the statement is true or false if the statement is false.
_____ 8. Very short distances should be measured in kilometers.
_____ 9. Distance is less important than direction in describing motion.
_____ 10. Words that describe direction include back and forth.
_____ 11. Speed is an example of a vector.
_____ 12. A horizontal line on a distance-graph represents a speed of zero.
_____ 13. Distance equals speed divided by time.
_____ 14. If an object’s speed changes so does its velocity.
_____ 15. Calculating acceleration is complicated when both speed and direction are changing.
_____ 16. You are accelerating when you jump up and down on a trampoline.
_____ 17. The SI unit for acceleration is km/s2.
Answers
Answer:
8.) There are millimeters, centimeters, meters and kilometers as the most commonly used units of metric measurement. If possible, rule out units that are definitely not appropriate to measure the object. Kilometers are about a half of a mile and are used to measure long distances, so that unit is not appropriate.
9.) Distance is less important than direction in describing motion? False.
10.) Back-and-forth definition, backward and forward; side to side; to and fro: a ... On the farm, the feed for chicks is significantly different from the roosters'; ______ not even ... As an adjective, back-and-forth describes a movement from one point to ... “Affect” vs. “Effect”: Use The Correct Word Every Time.
11.) 'Speed is a vector quantity' is a FALSE statement. Explanation: Vector quantity are those which have both magnitude as well as direction.
12.) Speed or velocity is plotted on the Y-axis. A straight horizontal line on a speed-time graph means that speed is constant. ... A straight line does not mean that the object is not moving!
13.) True
14.) TRUE - Objects with a changing speed also have a changing velocity. As such, an object with a changing speed also has a changing momentum.
15.) Changes in velocity are measured by acceleration. Acceleration reflects how quickly velocity is changing. It may involve a change in speed, a change in direction, or both.
16.) The stronger the push from the trampoline, the larger the acceleration and the higher the jump. In earlier work [1, 2], the motion on a trampoline was analysed in detail, showing the relation between the maximum force on the rider and the ratio between 'flight time' and contact time.
17.) Average Acceleration
Because acceleration is velocity in m/s divided by time in s, the SI units for acceleration are m/s2, meters per second squared or meters per second per second, which literally means by how many meters per second the velocity changes every second.
Hope this helps :)