Given:
Q = 0.0764 kJ = 764 J, heat input
W = -830 J, useful work done

From the 1st Law of Thermodynamics, the change in internal energy is
δE = Q - W
= 764 - (-830)
= 1594 J = 1.594 kJ

Answer: 1.59 kJ (two sig. fig.)

8 0

2 years ago

A statue is mounted on top of a 16 foot hill. From the base of the hill to where you are standing is 77 feet and the statue subt

DanielleElmas [232]

Consider right triangle with vertices B - base of the hill, S - top of the statue and Y - you. In this triangle angle B is right and angle Y is 13.2°. If h is a height of the statue, then the legs YB and BS have lengths 77 ft and 16+h ft.

You have lengths of two legs and measure of one acute angle, then you can use tangent to find h:

$\tan 13.2^{\circ}=\dfrac{\text{opposite leg}}{\text{adjacent leg}} =\dfrac{16+h}{77}, \\ \\ 0.2345=\dfrac{16+h}{77},\\ \\ 16+h=0.2345\cdot 77=18.0565,\\ h=18.0565-16=2.0565$ ft.

Answer: the height of the statue is 2.0565 ft.

8 0

1 year ago

Read 2 more answers

Daisy works at an ice-cream parlor. She is paid $10 per hour for the first 8 hours she works in a day. For every extra hour she

andre [41]

Answer:

80+(15x)

Step-by-step explanation:

10 times 8=80

1.5 times 10=15

so she gets 80 dollars for the first 8 hours then for every extra hour she gets 15 dollars

7 0

1 year ago

A triangle has side lengths of (1.3k+3.5m)(1.3k+3.5m) centimeters, (4.1k-1.6n)(4.1k−1.6n) centimeters, and (9.7n+4.4m)(9.7n+4.4m

Scorpion4ik [409]

Answer:

(5.4k+7.9m+8.1n) centimeters

Step-by-step explanation:

Given the side length of a triangle;

S1 = (1.3k+3.5m) cm

S2 = (4.1k-1.6n) cm

S3 = (9.7n+4.4m) cm

Perimeter of the triangle = S1+S2 + S3

Perimeter of the triangle = (1.3k+3.5m) + (4.1k-1.6n) + (9.7n+4.4m)

Collect the like terms;

Perimeter of the triangle = 1.3k+4.1k+3.5m+4.4m-1.6n+9.7n

Perimeter of the triangle = 5.4k+7.9m+8.1n

Hence the expression that represents the perimeter of the triangle is (5.4k+7.9m+8.1n) centimeters

5 0

1 year ago