Answer:
The rate of change of distance between the two ships is 18.63 km/h
Explanation:
Given;
distance between the two ships, d = 140 km
speed of ship A = 30 km/h
speed of ship B = 25 km/h
between noon (12 pm) to 4 pm = 4 hours
The displacement of ship A at 4pm = 140 km - (30 km/h x 4h) =
140 km - 120 km = 20 km
(the subtraction is because A is moving away from the initial position and the distance between the two ships is decreasing)
The displacement of ship B at 4pm = 25 km/h x 4h = 100 km
Using Pythagoras theorem, the resultant displacement of the two ships at 4pm is calculated as;
r² = a² + b²
r² = 20² + 100²
r = √10,400
r = 101.98 km
The rate of change of this distance is calculated as;
r² = a² + b²
r = 101.98 km, a = 20 km, b = 100 km
As opposed to ionic bonding in which a complete transfer of electrons occurs, covalent bonding occurs when two (or more) elements share electrons. Covalent bonding occurs because the atoms in the compound have a similar tendency for electrons (generally to gain electrons).
Answer:
Explanation:
Let the equal charges be Q .
Force between charges = k Q² / R where R is distance between charges , k = 9 x 10⁹.
Putting the charges
Force F = 9 x 10⁹ x Q² /( .72 x 10⁻²)²
= 17.36 x 10¹³ Q² N
This force equals weight so
17.36 x 10¹³ Q² = 15.7 x 10⁻³
Q² = .90 x 10⁻¹⁶
Q = .95 x 10⁻⁸
= 9.5 x 10⁻⁹
= 9.5 nC.
Answer:
Apply Newton's Second Law:
The acceleration of the object is proportional to the applied force.
Answer:
57.6
Explanation:
"Significant figures" refer to figures that have an actual contribution to a <em>number's value.</em>
They refer to all digits<u> except those with</u><em><u> </u></em><em><u>"leading zero,"</u></em> which means having a zero digit before a specific number. For example, in the number 0234, the significant figures are<em> 234. </em>
The rule for adding and subtracting significant figures is to <em>round off the answer to the least number of decimal places</em>. However, when it comes to multiplying and dividing significant figures, you have<em> round off the answer to the least number of significant digits.</em>
<u>Let's solve.</u>
21.4
+15
17.17
<u> 4.003</u>
57.573
Let's now round off to the<em> least number of decimal places</em>, which is the <em>tenths. </em>Since 0.5 is followed by a number greater than 5, we have to round it off to 6. Therefore, the answer is: 57.6
