Question

A car travels in a straight line covering a total distance of 90.0 miles in 60.0 minutes. Which one of the following statements concerning this situation is necessarily true? a. b. C. d. e. The average velocity of the car is 90.0 miles per hour in the direction of motion The speed of the car must be 90.0 miles per hour throughout the entire trip The velocity of the car is constant. The acceleration of the car must be non-zero. The first 45 miles must have been covered in 30.0 minutes. Answer:

Answer 1

a.it can only be true if the car travels in a straight line which is not given in the question.so it may be true but necessarily

b.speed of the car may change .so it may be true but not necessarily

c.velocity of the car may also change if the car changes its direction which is not implied by the question.Hence it may or may not be true

d-no data is given regarding accelaration,or whether the speed or velocity was constant or not,hence it may or may not be true

e-again no data is given regarding this,the car may cover less than,greater than or equal to 45 miles in the first 30 minutes.This statement is not necessarily true

therefore ,none of the statements are necessarily true