Acertain part of aircraft engine has a volume of
1.3ft3.
(a) find the weight of the piece when it is made ofiron.
(b) if the same piece is made of aluminum, find the weight
anddetermine how much weight is saved by using aluminum instead
ofiron.

419.25 lbs

Explanation:

Let iron density be 491.5 lb/ft3

and aluminum density be 169 lb/ft3

We can calculate the mass of iron that displaces 1.3ft3

Also the mass of aluminum that displaces 1.3 ft3

So by using aluminum, the airplane can save

638.95 - 219.7 = 419.25 lbs of weight

answer: a. same unit

explanation:

force is based upon mass and acceleration.the statement is not always true.

it can be explained from newton's second law of motion.

as per newton's second law of motion the rate of change of momentum is directly proportional to the applied force and takes place along the direction of force.

mathematically it can be written as -

                                              ⇒      

here   k is the proportionality constant whose value is 1.

                                                            [a is the acceleration=dv/dt]

hence we see that force not only depends on mass and acceleration but also on velocity and rate of change of mass. force f will depend on mass and acceleration only when mass is constant.

hence the statement that force is based upon mass and acceleration is false.