The speed of an object can be determined from the distance vs time graph.
You know that speed = distance/time
in the graph, distance/time = slope of the curve.
So SPEED IS GIVEN BY THE SLOPE of the curve in the graph.
● If the distance vs time curve is a straight line, parallel to time axis(x-axis), slope is 0. That means speed is 0. So the object is at rest.
● If the distance vs time curve is a straight line, with some non-zero slope; That means speed is nonzero and constant. So the object is in uniform motion.
● If the distance vs time curve is a curved, the slope is changing. That means speed is changing. So the object is in an accelerated motion.
Machines makes work easier by increasing the amount of force that is applied, and changing the direction in which the force is applied !! Hope it helped (p.s. I had this same question)
Explanation:
Acceleration is the change in speed over a given time period
Answer:
2.68 hours
Explanation:
A.) Suppose the wind blows out from the west (with the air moving east). The pilot should then head her plane to northwest direction to move directly north.
B.) Given that plane flies at a speed of 102 km/h in still air. And the wind blows out from the west (with the air moving east) at a speed of 46 km/h.
The plan resultant speed can be calculated by using pythagorean theorem.
Resultant Speed = Sqrt( 102^2 + 46^2 )
Resultant Speed = Sqrt( 12520)
Resultant speed = 111.89 km/h
From the definition of speed,
Speed = distance/time
Where distance = 300 km
Substitute the resultant speed and the distance into the formula.
111.89 = 300/time
Time = 300/111.89
Time = 2.68 hours
Therefore, it take her 2.68 hours to reach a point 300 km directly north of her srarting point
