please answer these questions whoever Will be giving me this answer I will mark as brainlest to his or her
Answers
Answer:
6. 2
7. a
8. 1
Explanation:
9. Generally, you can find that the pillars holding the track of metro trains have a broader base. This is because the broader base is quite stable equilibrium than other types. Hence, the stability is better and often preferred for the construction of metro train tracks.
10. When force is applied to the per unit area of a surface, it is called pressure.Pressure is defined as force per unit of area. ... Atmospheric pressure is defined as the pressure exerted on an object by the air above it.
Shoulder bags are provided with broad straps so as to increase the surface area on which the force is acting. By doing so, the pressure decreases. As P = FORCE / AREA If the bags were provided with thin straps, the pressure would have increased causing pain in shoulders.
11.i. Pour some water in the tube, balloon bulges out as in fig (b) because the water column exerts pressure at its bottom. ... Also, pressure exerted by the water P = Thrust/Area of bottom of the tube. This shows that a liquid exerts pressure at the bottom of the container in which it is kept.
ii. To show: A liquid exerts pressure at the bottom of the container. Procedure - Take a balloon and tie it at the lower end of a glass tube and hold vertically as in figure (a). Pour some water in the tube, balloon bulges out as in fig (b) because the water column exerts pressure at its bottom
iii. Take a plastic bottle in a tub , fill it with water,make 4 holes around the bottle at equal heights, we can see that water flows out with equal pressure from all holes. thus we observe that liquids exert equal pressure at same depth.
12. We do not feel the pressure of the atmosphere around us, because the pressure in our bodies is roughly the same as the atmospheric pressure outside. Therefore, both the forces acting on our bodies cancel out and we do not feel uncomfortable.
13. the ball after rolling stops as rest after sometime is just because friction of land and air friction.
14.a. Magnetic Force is a force that attracts certain metal objects (like iron and iron filings) towards a magnet. ... This is because the comb is charged because of the rubbing on your hair and it attracts uncharged objects like paper.
b. Gravitational force is the force of attraction on a body by earth. Example - Leaves and fruits fall from a tree downwards towards the ground due to the gravitational pull. ... Leaves Add fruits that fall from the tree downwards.
c. The electrostatic force is the force that exists between electrically charged particles or objects at rest. Examples of electrostatic forces: ... When I do iron my silk or cotton cloth and keep it right in front of me, they just cling on to my body. Lightning is also another example of electrostatic force."
d. Frictional Force is a force that acts on all moving objects by the surface which it is in contact with. Eg: A ball rolling on the ground encounters friction by the ground surface and it eventually comes to a halt.
15. sorry don't know this answer.
Answer:
6) Force cannot change the: Mass of the object (2)
7) The pull of the earth is a force called: Gravitational Force (1)
8) If force is applied on a smaller area of contact, the pressure exerted by it is: Greater (1)
9) To make sure that the weight of the metro train does not put much pressure on the tracks.
10) Pressure is force divided by surface area of contact. Shoulder bags have wider straps so that the weight of the bag gets evenly distributed causing less pressure on the shoulders.
11)
i) Make 4 vertical holes in a bottle and fill the bottle
ii) Make a hold on 1 side, and attach a balloon
iii) Make holes at the same height from the base at the bottom.
i)
12) Because our body exerts a (slightly) greater pressure than the atmospheric pressure from inside.
13) Frictional force
14)
a) Magnetic force - The force exerted between two magnets. Ex: in a magnet
b) Gravitational Force - The force exerted between any two particles. Ex: The earth
c) Electrostatic force - The force exerted between two charged particles in rest. Ex: When a comb is rubbed with a wooled cloth
d) Frictional Force - The force that opposes motion. Ex: The resisting force when an object moves.
15)
a) Because pressure = force/area, many nails divided the body weight, and did not cause pain.