The answer is B. On a sunny day, the air over a lake will be cooler than the air over the bordering land.
Answer:
9704.6 J
Explanation:
Total Thermal Energy
= Energy required to bring gold to melting point + Energy required to change the state of gold from solid to liquid
= mcT + <em>m</em><em>l</em><em>f</em><em> </em><em> </em>[bolded is energy used to bring gold to melting point, <em>i</em><em>t</em><em>a</em><em>l</em><em>i</em><em>c</em><em>i</em><em>s</em><em>e</em><em>d</em><em> </em><em>i</em><em>s</em><em> </em><em>s</em><em>t</em><em>a</em><em>t</em><em>e</em><em> </em><em>c</em><em>h</em><em>a</em><em>n</em><em>g</em><em>e</em><em> </em><em>o</em><em>f</em><em> </em><em>g</em><em>o</em><em>l</em><em>d</em><em> </em><em>f</em><em>r</em><em>o</em><em>m</em><em> </em><em>s</em><em>o</em><em>l</em><em>d</em><em> </em><em>t</em><em>o</em><em> </em><em>l</em><em>i</em><em>q</em><em>u</em><em>i</em><em>d</em><em>]</em>
= (0.0500)(126)(1063 - 21) + <em>(</em><em>0</em><em>.</em><em>0</em><em>5</em><em>0</em><em>0</em><em>)</em><em>(</em><em>6</em><em>.</em><em>2</em><em>8</em><em> </em><em>×</em><em> </em><em>1</em><em>0</em><em>^</em><em>4</em><em>)</em>
= <u>9704.6</u><u> </u><u>J</u>
<u>S</u><u>o</u><u>l</u><u>u</u><u>t</u><u>i</u><u>o</u><u>n</u><u>-</u><u>1</u><u>:</u><u>-</u>

<u>S</u><u>o</u><u>l</u><u>u</u><u>t</u><u>i</u><u>o</u><u>n</u><u>:</u><u>-</u><u>2</u>

<u>S</u><u>o</u><u>l</u><u>u</u><u>t</u><u>i</u><u>o</u><u>n</u><u>:</u><u>-</u><u>3</u>

<u>S</u><u>o</u><u>l</u><u>u</u><u>t</u><u>i</u><u>o</u><u>n</u><u>:</u><u>-</u><u>4</u>

<u>S</u><u>o</u><u>l</u><u>u</u><u>t</u><u>i</u><u>o</u><u>n</u><u>:</u><u>-</u><u>5</u>

<u>S</u><u>o</u><u>l</u><u>u</u><u>t</u><u>i</u><u>o</u><u>n</u><u>:</u><u>-</u><u>6</u>

<u>S</u><u>o</u><u>l</u><u>u</u><u>t</u><u>i</u><u>o</u><u>n</u><u>:</u><u>-</u><u>7</u>

<u>S</u><u>o</u><u>l</u><u>u</u><u>t</u><u>i</u><u>o</u><u>n</u><u>:</u><u>-</u><u>8</u>

<u>S</u><u>o</u><u>l</u><u>u</u><u>t</u><u>i</u><u>o</u><u>n</u><u>:</u><u>-</u><u>9</u>

<u>S</u><u>o</u><u>l</u><u>u</u><u>t</u><u>i</u><u>o</u><u>n</u><u>:</u><u>-</u><u>10</u>

Answer:

Explanation:
It is given that,
Speed of the projectile is 0.5 v. Let h is the height above the ground. Using the first equation of motion to find it.


Initial speed of the projectile is v and final speed is 0.5 v.


g is the acceleration due to gravity
Let h is the height above the ground. Using the second equation of motion as :



So, the height of the projectile above the ground is
. Hence, this is the required solution.