10.20) Perform the following conversions: (a) 0.912 atm to torr,(b) 0.685 bar to kilopascals, (c) 655 mm Hg to atmospheres,(d) 1.323 * 105 Pa to atmospheres, (e) 2.50 atm to psi. Perform the following conversions: (a) 0.912 atm to torr, (b) 0.685 bar to kilopascals, (c) 655 mm Hg to atmospheres, (d) 1.323 * 105 Pa to atmospheres, (e) 2.50 atm to psi.

(a)  0.912 atm = 693.12 torr

(b)  0.685 bar = 68.5 kpa

(c)  655 mm Hg = 0.8618 atm

(d)  1.323x10⁵ Pa = 1.305 atm

(e)  2.50 atm = 36.74 psi

Explanation:

(a) 0.912 atm to torr

We know that 1 atmospheric pressure (Atm) is equal to 760 torr (mm Hg)

so 0.912*760 = 693.12 torr

(b) 0.685 bar to kilopascals

We know that 1 bar is equal to 100 kpa

so  0.685*100 = 68.5 kpa

(c) 655 mm Hg to atmospheres

We know that 1 atmospheric pressure (Atm) is equal to 760 torr (mm Hg)

so 655/760 = 0.8618 atm

(d) 1.323x10⁵ Pa to atmospheres

We know that 1 atm is equal to 101,325 Pascals

so  1.323x10⁵/101,325 = 1.305 atm

(e) 2.50 atm to psi

We know that 1 atm is equal to 14.696 pound-force per square inch (psi)

so 2.50*14.696 = 36.74 psi

answer: at 24 february, 2014 the population gets twice of its initial population.

explanation:

since we have given that

the population for alpha city, t years after january 1, 2004 is given as

first we find out the initial population, i.e. t=0,

so, our quadratic equation becomes,

according to question, we have said that if the population has twice its initial population, then it becomes

so, time taken to reach this above mentioned population is given by

now, we know that time can't be negative so, we take t=9.149 years.

hence, at 24 february, 2014 the population gets twice of its initial population.

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.