Aship leaves a port p and travels 30 km due north . then it changes course and travels 20 km in a direction 30° east of north to reach port r. calculate the distance from p to r.

The distance between P and R is equal to the net displacement of the ship in going from port P to port R

Vector P = 30 km North

Vector R = 20 km 30° east of north

Now, the angle between Vector P and vector R = 90° + 30 ° = 120°

Using the formula to find the addition of two vectors:

Resultant =

Plugging the values:

Resultant = 26.457 Km

The distance from P to R is 26.457 km

close lines strong magnet less close weaker

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-the first industrial use of geothermal energy began near pisa, italy in late 18th century

-in 1904, italian scientist piero ginori conti invented the first geothermal electric power plant in which steam was used to generate the power

-with the above experiment, the first geothermal plant in usa started in 1922 with a capacity of 250 kilowatts

-however, in 1946 first ground-source geothermal heat pump installed at commonwealth building in portland, oregon

-during the 1960’s, pacific gas and electric began operation of first large scale geothermal power plant in san francisco, producing 11 megawatts

-in 1973, when oil crisis began many countries began looking for renewable energy sources and by 1980’s geothermal heat pumps (ghp) started gaining popularity in order to reduce heating and cooling costs

-as effect of climate change started showing results, governments of various countries joined hands to fight against it, for which kyoto protocol was signed in japan in 1997, laid out emission targets for rich countries and required that they transfer funds and technology to developing countries, 184 countries have ratified it

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