physics kbat

Question 1

Use tight and light suit

Answer 1

Less air friction

Question 2

Use spikes shoes

Answer 2

Better grip support while running and prevent slippery

Question 3

Landing on sandy ground

Answer 3

Increase time of impact during landing , reduce impulsive force and prevent injury

Question 4

The athlete has to sprint before jumping

Answer 4

Can increase kinetic energy

Question 5

Athlete has to bend the body during fall

Answer 5

Increase the time impact , reduce impulsive force

Question 6

Choose metal with high strength and hardness

Answer 6

Even under pressure the shape will not change/break easily

Question 7

Frame of rocket is made of low density metal

Answer 7

Lighter, can accelerate faster.

Question 8

Multistage rocket invented

Answer 8

Each stage has burning fuel, pump and combustion chamber. It will slip off when fuel of each chamber completely burn. When the mass decreases, the acceleration increases

Question 9

Rocket need to carry a tank of oxygen

Answer 9

To enable the combustion of fuel in space

Question 10

Silver color rocket

Answer 10

Reflect light efficiently so the temperature of the rocket will
not rise easily

Question 11

Cover the body of rocket with heat insulator

Answer 11

friction between air and the body will increase heat. The insulator will reduce heat conductivity

Question 12

Aerodynamic shape

Answer 12

Reduce air friction, move faster

Question 13

Nose cone or bullet shape on top of body

Answer 13

To improve the aerodynamic of rocket

Question 14

45 angle of launching

Answer 14

The rocket can travel maximum distance

Question 15

The volume of water is half or 1/3 from the whole volume

Answer 15

Not too heavy so as to increase the momentum and the impulsive force

Question 16

Attach 3 or 4 fins at the tail of rocket and space out equally

Answer 16

Rocket will move smoothly and stable with no tumble.

Question 17

Attach parachute

Answer 17

decrease the speed of falling due to air resistance

Question 18

Semicircular curve shape track

Answer 18

Exchange between kinetic energy and gravitational potential can happen easily

Question 19

The slope slightly increase and decrease

Answer 19

Easy to oscillates cause by smooth changing of energy

Question 20

Decrease the diameter of the nozzle

Answer 20

Exhaust gas can be ejected at higher speed

Question 21

Increase number of blades

Answer 21

Can draw in more air into the engine

Question 22

Increase more fuel injectors

Answer 22

More fuel to be burnt to produce greater thrust/force

Question 23

Lower height of seat

Answer 23

Lower center of gravity, more stable and safer during turning.

Question 24

Bigger width tires

Answer 24

Bigger surface area, better support, low pressure acts on the tyres and more friction when breaking.

Question 25

Less thread pattern of tires

Answer 25

Increase the surface area in contact with the road for better gripping

Question 26

Smaller mass

Answer 26

Light, small inertia so motorcycle can moves faster

Question 27

Reduce pain and protect player’s hands when catching the ball

Answer 27

Wear glove

Question 28

Lengthen the time impact, reduce impulsive force.

Answer 28

Use soft material for glove

Question 29

To reduce heat loss and maintain the body temperature of player

Answer 29

Wear cloth which made from high specific heat capacity material

Question 30

The stud will sink into ground and give good gripping without slipping

Answer 30

Base of shoes has stud

Question 31

The load of lorry should be divided into many smaller tanks

Answer 31

To reduce effect of inertia

Question 32

Use more tires

Answer 32

Pressure will be distributed to all tires, able to carry more loads.

Question 33

Far gap distance between tractor and trailer

Answer 33

Provide space and easier for turning of the tractor.