3. Mary Lou is running errands for her mother. She leaves her house and goes 1 mile north to the bakery. She then goes 2.5 miles south to get her hair cut. She continues south for 1.5 miles to
check out a book from the library. She then goes 0.75 miles north to meet a friend. This entire
voyage lasts 3 hours.
a) What is the total distance traveled? 6
b) What is the total displacemen 7
c) What was her average speed?
8
d) What was her average velocity

Explanation:

a) The total distance travelled by Mary will be addition of the distances travelled in all directions.

Total distance travelled = 1 mile + 2.5 mile + 1.5miles + 0.75 miles

Total distance travelled = 5.75 miles

Hence the total distance traveled by Mary in her entire journey is 5.75 miles

b) Displacement is the total distance travelled in a specified direction. The displacement = 2.5 miles + (1.5- 0.75) miles = 3.25 miles

c) Speed is the change in distance with respect to time.

Speed = distance/time

Speed = 5.75/30

Speed = 0.193mi/hr

d) Average velocity is the change in displacement  with respect to time.

Velocity = displacement/time

Velocity = 3.750/30

Velocity = 0.125mi/hr

when a device is used in a circuit in which the voltage is 81 v, the current flowing through the device is 3 a. what is the resistance of the device?

a. 27 ω

b. 40.5 a

c. 243 ω

d. 243 a

the correct answer is a. 27