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AnnZ [28]
2 years ago
5

A 0.14-km wide river flows with a uniform speed of 4.0 m/s toward the east. It takes 20 s for a boat to cross the river to a poi

nt directly north of its departure point on the south bank. What is the speed of the boat relative to the water
Physics
1 answer:
Dmitry [639]2 years ago
7 0

Answer:

The right approach is "8.1 m/s". A further explanation is provided below.

Explanation:

According to the table,

Speed of Boat

= \frac{s}{t}

V_b=\frac{140}{20}

V_a = 4 \ m/s

V_B = 7 \ m/s

Now,

⇒  (V_{relative})^2 = (7)^2+(4)^2

or,

⇒  (V_r)^2=49+16

              =65

         V_r=\sqrt{65}

              =8.1 \ m/s

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5 0
3 years ago
(a) Calculate the acceleration due to gravity on the surface of the Sun.
Ira Lisetskai [31]
<h2>a)Acceleration due to gravity on the surface of the Sun is 274.21 m/s²</h2><h2>b) Factor of increase in weight is 27.95</h2>

Explanation:

a) Acceleration due to gravity

                      g=\frac{GM}{r^2}

 Here we need to find acceleration due to gravity of Sun,

                G = 6.67259 x 10⁻¹¹ N m²/kg²

    Mass of sun, M = 1.989 × 10³⁰ kg

    Radius of sun, r = 6.957 x 10⁸ m

Substituting,

                g=\frac{6.67259\times 10^{-11}\times 1.989\times 10^{30}}{(6.957\times 10^8)^2}\\\\g=274.21m/s^2

Acceleration due to gravity on the surface of the Sun = 274.21 m/s²

b) Acceleration due to gravity in earth = 9.81 m/s²

   Ratio of gravity = 274.21/9.81 = 27.95

   Weight = mg

  Factor of increase in weight = 27.95

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3 years ago
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Answer:

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navik [9.2K]

Explanation:

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3 years ago
Which of these is a chemical control used to help control invasive species?
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Answer:

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