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3 years ago

Consider an elevator with a table and a book on top of the table. The mass of the table is 10kg and the mass of the book is 2kg.

Physics

1 answer:

Step2247 [10]3 years ago

4 0

Newton's second law allows us to find the force of the block on the table is 126 N

Newton's second law says that the net force is proportional to the product of the mass and the acceleration of the body

Σ F = m a

Where the bold letters indicate vectors, m is the mass and the acceleration of the body

A free body diagram is a diagram where the forces are represented without the details of the bodies, in the attached we can see a free body diagram of the system.

Let's start by finding the acceleration of the elevator with kinematics

v = v₀ + a t

a = $\frac{v-v_o}{a}$

Where v and v₀ are the current and initial velocity, respectively, at acceleration and t is the time

a = $\frac{8-1}{2}$

a = 3.5 m / s²

Let's write Newton's second law for each body

The book

N₂ - W₂ + N₁ = m a

Table

N₁ - W₁ - W₂ = M a

W₁ = Mg

W₂ = mg

N₁ = (M + m) g + M a

N₁ = (10 + 2) 9.8 + 10 3.5

N₁ = 152.6 N

This is the reaction of the earth to the support of the block and the table

N₂ = ma + m g - N₁

N₂ = m ( a +g) - N₁

N₂ = 2 (3.5 + 9.8) - 152.6

N₂ = 26.6 - 152.6

N₂ = -126 N

The negative sign indicates that the direction is opposite to the one assigned, this is the action of the block on the table.

In conclusion using Newton's second law we can find the forces of the block on the table is 126 N

Learn more here: brainly.com/question/19860811

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Answer:

8 seconds, Answer choice C.

Explanation:

The information they give us about the speed of the cat, is from the point at which the dog started chasing it (that velocity being 10 m/s).

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Since all units for the physical quantities involved were given in the SI system, the answer comes also in the SI units of time: "seconds"

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3 years ago

A projectile is fired from the ground (you can assume the initial height is the same as the ground) in a field so there are no o

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Answer:

(A) 111.77m

(B) 9.07m

(D)20.54m/s

Explanation:

step 1 " we have to calculate the time it took the projectile to get to its maximum height

(a) t = usinθ/g

= 49sin 33/9.81

49×0.5446/9.81

=2.72s

the horizontal distance = ucosθ×t , because the projectile horizontal motion is unaffected by the force of graavity

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55.8 = 49cos33 ×t

t = 55.8/49cos33

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Answer:

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Explanation:

We are given that

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Answer:

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