Whether the work is positive or negative if a chicken scratching the ground.

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Answer 1

Question

Chapter 7, Problem 7.7CQ

(a)

To determine

Whether the work is positive or negative if a chicken scratching the ground.

(b)

To determine

Whether the work is positive or negative if a person is studying a book.

(c)

To determine

Whether the work is positive or negative if a crane lifts a bucket of concrete.

(d)

To determine

Whether the work is positive or negative if a crane lift a bucket and the gravitational force act on the bucket.

(e)

To determine

Whether the work is positive or negative if the leg muscles of a person in the act of sitting down.

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Question B3 Consider the following FLRW spacetime: t2 ds² = -dt² + (dx² + dy²+ dz²), t2 where t is a constant. a) State whether this universe is spatially open, closed or flat. [2 marks] b) Determine the Hubble factor H(t), and represent it in a (roughly drawn) plot as a function of time t, starting at t = 0. [3 marks] c) Taking galaxy A to be located at (x, y, z) = (0,0,0), determine the proper distance to galaxy B located at (x, y, z) = (L, 0, 0). Determine the recessional velocity of galaxy B with respect to galaxy A. d) The Friedmann equations are 2 k 8πG а 4πG + a² (p+3p). 3 a 3 [5 marks] Use these equations to determine the energy density p(t) and the pressure p(t) for the FLRW spacetime specified at the top of the page. [5 marks] e) Given the result of question B3.d, state whether the FLRW universe in question is (i) radiation-dominated, (ii) matter-dominated, (iii) cosmological-constant-dominated, or (iv) none of the previous. Justify your answer. f) [5 marks] A conformally…

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Answer 2

Question

Chapter 7, Problem 7.7CQ

(a)

To determine

Whether the work is positive or negative if a chicken scratching the ground.

(b)

To determine

Whether the work is positive or negative if a person is studying a book.

(c)

To determine

Whether the work is positive or negative if a crane lifts a bucket of concrete.

(d)

To determine

Whether the work is positive or negative if a crane lift a bucket and the gravitational force act on the bucket.

(e)

To determine

Whether the work is positive or negative if the leg muscles of a person in the act of sitting down.

Expert Solution & Answer

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Check out a sample textbook solution

See solution

Answer 3

Question

Chapter 7, Problem 7.7CQ

(a)

To determine

Whether the work is positive or negative if a chicken scratching the ground.

(b)

To determine

Whether the work is positive or negative if a person is studying a book.

(c)

To determine

Whether the work is positive or negative if a crane lifts a bucket of concrete.

(d)

To determine

Whether the work is positive or negative if a crane lift a bucket and the gravitational force act on the bucket.

(e)

To determine

Whether the work is positive or negative if the leg muscles of a person in the act of sitting down.

Expert Solution & Answer

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Check out a sample textbook solution

See solution

Answer 4

Question

Chapter 7, Problem 7.7CQ

(a)

To determine

Whether the work is positive or negative if a chicken scratching the ground.

(b)

To determine

Whether the work is positive or negative if a person is studying a book.

(c)

To determine

Whether the work is positive or negative if a crane lifts a bucket of concrete.

(d)

To determine

Whether the work is positive or negative if a crane lift a bucket and the gravitational force act on the bucket.

(e)

To determine

Whether the work is positive or negative if the leg muscles of a person in the act of sitting down.

Expert Solution & Answer

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Check out a sample textbook solution

See solution

Answer 5

Chapter 7, Problem 7.7CQ

(a)

To determine

Whether the work is positive or negative if a chicken scratching the ground.

(b)

To determine

Whether the work is positive or negative if a person is studying a book.

(c)

To determine

Whether the work is positive or negative if a crane lifts a bucket of concrete.

(d)

To determine

Whether the work is positive or negative if a crane lift a bucket and the gravitational force act on the bucket.

(e)

To determine

Whether the work is positive or negative if the leg muscles of a person in the act of sitting down.

Answer 6

Chapter 7, Problem 7.7CQ

(a)

To determine

Whether the work is positive or negative if a chicken scratching the ground.

Answer 7

Chapter 7, Problem 7.7CQ

(a)

To determine

Whether the work is positive or negative if a chicken scratching the ground.

Answer 8

(b)

To determine

Whether the work is positive or negative if a person is studying a book.

Answer 9

(b)

To determine

Whether the work is positive or negative if a person is studying a book.

Answer 10

(c)

To determine

Whether the work is positive or negative if a crane lifts a bucket of concrete.

Answer 11

(c)

To determine

Whether the work is positive or negative if a crane lifts a bucket of concrete.

Answer 12

(d)

To determine

Whether the work is positive or negative if a crane lift a bucket and the gravitational force act on the bucket.

Answer 13

(d)

To determine

Whether the work is positive or negative if a crane lift a bucket and the gravitational force act on the bucket.

Answer 14

(e)

To determine

Whether the work is positive or negative if the leg muscles of a person in the act of sitting down.

Answer 15

(e)

To determine

Whether the work is positive or negative if the leg muscles of a person in the act of sitting down.

Answer 16

Expert Solution & Answer

Answer 17

Expert Solution & Answer

Answer 18

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Answer 19

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Whether the work is positive or negative if a chicken scratching the ground.

Solution Summary: The author explains that work done is positive if a chicken is scratching the ground because it is in the direction of the force.

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Whether the work is positive or negative if a chicken scratching the ground.

Whether the work is positive or negative if a person is studying a book.

Whether the work is positive or negative if a crane lifts a bucket of concrete.

Whether the work is positive or negative if a crane lift a bucket and the gravitational force act on the bucket.

Whether the work is positive or negative if the leg muscles of a person in the act of sitting down.

Want to see the full answer?

Chapter 7 Solutions