Answer:
4 option is correct ........
Answer:
a) mass=density x volume= 2400 x 0,20=480 Kg
b) weight= 480 x 9,81 = 4708,8 N
Answer:
a) about 14.577 kg
b) 300 N
Explanation:
b) In order for the acceleration to be the same for each mass, the 800 N force must be divided between the boxes in proportion to their mass. That is, the net force on the 5M mass must be 5/8 of the total force, or 500 N. Then the tension in the rope is 800 N -500 N = 300 N, which is 3/8 of 800 N.
Tension: 300 N
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a) The total mass is 8M, and the total normal force on the floor is ...
F = ma = (8M)(9.8 m/s^2)
The friction force is 0.7 times this, and is equal to the 800 N force pulling on the boxes.
800 N = (8M)(9.8 m/s^2)(0.7)
M = 800/(8·9.8·0.7) kg ≈ 14.577 kg
Because the elevator moves at a constant speed, it's in equilibrium and the net force acting on it is zero. Then the tension in the cable exactly equals the magnitude of the elevator's weight, which is
(3000 kg) (9.80 m/s²) = 29,400 N
Ans: C) Solid
Explanation: We will look into different states
A) Liquid : In liquid state molecules are not very tightly bound to each other. So, they have no fixed shape . They take the shape of container in which they are kept.
B) Gas : In gaseous state molecules are very loosely bound so they have very less intermolecular forces so they have much more freedom of movement.So, it will be also not correct.
D) Plasma : In Plasma state approximately equal amount of positive or negative charges are there, although its a type of hot ionized gaseous state but but due its different properties then other gases it is considered the 'fourth' state. And it also can't maintain it's definite shape and volume.So we will eliminate that also.
C) Solid : Finally we are left with solid state. Here molecules are tightly bound to each other . So, it doesn't change its shape and volume when kept in different container.
So 'Solid' state is the correct choice.
Hope it helps!!!
