Question

1-      You can find your own mass in kg with the following information: 1.0 kg weighs about 2.2 lb. on Earth. a) What is your mass in kg? b) What is your weight in newtons?

2-      Gunter the weightlifter can lift a 230.0-kg barbell overhead on Earth. The acceleration due to gravity on the sun is 274 m/s2. a) Would the barbells be heavier on the sun or on Earth? b) How much (in newtons) would the barbells weigh on the sun (if it were possible to stand on the sun without melting)?

3-      Sammy Sosa swings at a 0.15 kg baseball and accelerates it at a rate of 3.0 104 m/s2. How much force does Sosa exert on the ball

Answer 1

1.a)

Lets say u weigh 100lbs.

Use ratios to figure out the mass in kg. So if 1.0kg = 2.2 lbs, it means that 1.0lb = 1.0 /

2.2 kg which equals 1.0lb = 0.4545kg, so 100 lbs = 100 x 0.4545 kg

100lbs = 45 kg...thats u mass

b)

Ur weight is essentially the force of Gravity:

Force = mass time acceleration

u kno the mass (45 kg) and the acceleration (9.8 m/s^2)

u multiply the two to get 441N which is the force of gravity, which equals ur weight.

2)

a) kind of silly, since the barbells would vaporize on the sun (right after you did). But I'll go with the cliched physics answer, "Why, yes! They'd be heavier on the sun!" (By the ratio of 274 : 9.8.)

If you start with F=ma,

you get:

F=(230.0kg)(274m/s/s)

F= 63,020 N

3)

Force = Mass * Acceleration

= 0.15 kg * 3.0 * 10^4 ms^-2

= 4500 kg ms^-2 = 4500 N.