1. A COMPACT CAR HAS A MASS OF 950 KG AND AN OVERALL EFFICIENCY OF 23.0% (THAT I

Question

1. A COMPACT CAR HAS A MASS OF 950 KG AND AN OVERALL EFFICIENCY OF 23.0% (THAT IS IT CONVERTS 23.0% OF CHEMICAL ENERGY STORED IN THE GASOLINE INTO WORK DONE BY THE DRIVE TIRES PUSHING ON THE ROAD)

(FOR 1B AND 1C ASSUME CONSTANT ACCELERATION OF         

     A)  IF ONE GALLON OF GASOLINE CONTAINS     1.34?10^(8)  JOULES OF STORED CHEMICAL ENERGY, FIND THE AMOUNT OF GASOLINE (IN GALLONS) USED WHEN THE CAR ACCELRATES FROM REST TO 32 M/S (WITH NO AIR  OR ROAD FRICTION AND ON THE LEVEL).

   B) REPEAT PART A FOR THE CASE WHERE THE UNIFORM ACCELERATION AND AN AVERAGE FRICITIONAL FORCE TOTAL AIR AND ROAD OF 370 N

   C) REPEAT PART B FOR THE CASE WHERE THE UNIFORM ACCELERATION IS UP A 5.00% SLOPE.

   D) THE MILEAGE CLAIMED FOR THE CAR IS 60.8 KM/GALLON AT  A SPEED OF 32.0 M/S. WHAT POWER IS DELIVERED TO THE WHEELS( TO OVERCOME FRICTIONAL EFFECTS) WHEN THE CAR IS DRIVING AT 32.0M/S ON A LEVEL ROAD AND WHAT IS THE AVERAGE FRICTIONAL FORCE AT THIS SPEED ON THIS CAR?

2. A SMALL MASS M RESTS AT THE TOP OF A SMOOTH (FRICTIONLESS) HEMISHPERE OF RADIUS R. IT IS DISPLACED SLIGHTLY SO THAT IT SLIDES FROM REST DOWN THE HEMISPHERE. IT REMAINS IN CONTACT WITH THE SURFACE UNTIL IT REACHES THE ANGLE       . FROM THIS POINT ON IT LOSES CONTACT WITH THE SURFACE AND FOLLOWS A FREE-FALL PARABOLIC PATH. FIND THE ANGEL        . HINT: YOU MUST USE BOTH CENTRIPETAL FORCE ANALYSIS AND ENERGY ANALYSIS TO SOLVE THIS PROBLEM. AT THE POINT WHERE M LEAVES THE SPHERE, THE NORMAL FORCE IS ZERO.

Explanation / Answer

A) total mechanical energy required = change in kinetic energy = 0.5 * mass * velocity^2
so.. total mechanical energy required = 0.5 * 950 * 32^2 = 486400 Joules

so.. as efficiency = 23 % , the chemical energy required = 486400 / 0.23 = 2114782.6087 Joules

so... amount of gasoline = 2114782.6087/ ( 1.34 * 10^8 ) = 0.015782 Gallons

B)
let the acceleration be a and the distance travelled be s

so.. v^2 = u^2 + 2*a*s

PLEASE MENTION THE VALUE OF CONSTANT ACCELERATION FOR PART B SO THAT I CAN SOLVE THE REST

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.