. by newton’s second law, f=ma (w-r=ma, where w = weight, r = air resistance) . when we let...

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Page 1: . By Newton’s Second law, F=ma (W-R=ma, where W = weight, R = air resistance) . When we let the parachute fall down, the plastic bag is opened and
Page 2: . By Newton’s Second law, F=ma (W-R=ma, where W = weight, R = air resistance) . When we let the parachute fall down, the plastic bag is opened and
Page 3: . By Newton’s Second law, F=ma (W-R=ma, where W = weight, R = air resistance) . When we let the parachute fall down, the plastic bag is opened and
Page 4: . By Newton’s Second law, F=ma (W-R=ma, where W = weight, R = air resistance) . When we let the parachute fall down, the plastic bag is opened and
Page 5: . By Newton’s Second law, F=ma (W-R=ma, where W = weight, R = air resistance) . When we let the parachute fall down, the plastic bag is opened and

. By Newton’s Second law, F=ma (W-R=ma , where W = weight , R = air resistance)

. When we let the parachute fall down, the plastic bag is opened and air resistance would increase so that the net downward force acting on the parachute will decrease.

. Net force decreases, acceleration also decreases.. Acceleration of the parachute decreases, so the landing velocity of the parachute also decreases.

Page 6: . By Newton’s Second law, F=ma (W-R=ma, where W = weight, R = air resistance) . When we let the parachute fall down, the plastic bag is opened and

• Before this experiment, the egg had already been broken. We threw the parachute from 4th floor onto the playground of our school.

• The weight of our parachute is about 100g.

• The time taken for the parachute to fall was about 7 second.

Page 7: . By Newton’s Second law, F=ma (W-R=ma, where W = weight, R = air resistance) . When we let the parachute fall down, the plastic bag is opened and

• A parachute can effectively make thing land more safely.• The surface of the parachute is very important to make it

land slowly.• The weight of the parachute should not be too large.

Page 8: . By Newton’s Second law, F=ma (W-R=ma, where W = weight, R = air resistance) . When we let the parachute fall down, the plastic bag is opened and

• Chan Mei Wa 4C (2)• After this experiment, I learned more about Newton’s second law and

the theory of the parachute. I think that Physics is very useful in our life. It is difficult to design a parachute. But I was disappointed that this experiment was not successful.

• Choi Wing Ki 4C (6)• The experiment was very interesting, it also let us know the relations

hip between gravity and air resistance. During the experiment, our egg arrived at the ground. We can know that if the parachute is larger, air resistance will be larger too. It can lower the landing speed of an object, thus the object can arrive at the ground safely.

Page 9: . By Newton’s Second law, F=ma (W-R=ma, where W = weight, R = air resistance) . When we let the parachute fall down, the plastic bag is opened and

• Wan Wai Kit 4C (35)• After I've finished this physics project, I've learnt a lot from it ,such as ho

w to behave in team work and how to apply the knowledge that we had learnt to make this project work and I think we have done a great job although our parachute didn't win any award. But I am still overjoyed with it.

• Lin Lai Yan 4C (13)• I think this project is a project that require skills. We need to apply some

physics theory and spent a lot of time to test it. We had spent a lot of time for it. At the end ,even though we can’t get any award, we learned so much. We had learnt how to solve problems.

Page 10: . By Newton’s Second law, F=ma (W-R=ma, where W = weight, R = air resistance) . When we let the parachute fall down, the plastic bag is opened and

• Ho Siu Lun 4C (21)This Project make me study more about air resistance and net force acting on object. How can we make use of air resistance to let the egg fall down and does not break on landing?