A) A man with a mass of 80 kilogram (kg) is carrying a box with a mass of 22,5 kilogram (kg). The gravitational field strength on earth is 9.8 Newton/kilogram (N/kg). Calculate the weight of this man and the box together.
B) On the moon this man's weight would be 165 Newton. calculate the gravitational field strength of the moon
W=m⋅g
Slide 8 - Diapositive
Calculating pressure
A woman weighing 76 kg is wearing high heels to the zoo. She goes to see an elephant with a mass of 5221 kg. One of her heels has a total area of 8.4 cm2. One of the elephants feet has an area of 301 cm2.
a) Without making calculations, make an estimation of wether the elephant or the women applies a greater pressure to the ground. Write down your reasoning.
b) Calculate the pressure the women applies to the ground in N/m2.
c) Calculate the pressure the elephant applies to the ground N/m2.
P=AF
W=m⋅g
Slide 9 - Diapositive
Homework
Read paragraph 8.3
Do the workbook exercises of 8.3
Slide 10 - Diapositive
Learning goals
By the end of this lesson you will be able to:
Explain what pressure is, name the formula for pressure and do calculation exercises about pressure.
Explain what weight is, name the formula for weight and do calculation exercises about weight.