Question
A boy walks 10 m due west and 10m due south.What is the displacement.[2]a girl walks 12m northwards,5m eastwards and 7m southwards.Calculate her total displacement[3]a man walks 5km south and 3km in the direction 60 degree west of south.Calculate his distance from starting point.
Answers
Steve
these all just use the Pythagorean Theorem, or the distance formula, which is the same.
Just figure out the final location, and then use the formula.
For #1,
(0,0) -> (-10,0) -> (-10,-10)
distance is √(10^2+10^2) = 14.1
Just figure out the final location, and then use the formula.
For #1,
(0,0) -> (-10,0) -> (-10,-10)
distance is √(10^2+10^2) = 14.1
Manu Danso Dennis
Using Pythagoras theorem the answer is 14.1 for question 1
henry2,
2. Disp. = 12i + 5 - 7i = 5 + 5i = 7.07m[45o].
3. All angles are measured CW from +y-axis.
Disp. = 5[180o] + 3[240o].
X = 5*sin180 + 3*sin240 = -2.60 km.
Y = 5*Cos180 + 3*Cos240 = -6.5 km.
Disp. = -2.60 + (-6.5)I = 7.0[22o] W. of S. = 7.0km[202o] CW.
3. All angles are measured CW from +y-axis.
Disp. = 5[180o] + 3[240o].
X = 5*sin180 + 3*sin240 = -2.60 km.
Y = 5*Cos180 + 3*Cos240 = -6.5 km.
Disp. = -2.60 + (-6.5)I = 7.0[22o] W. of S. = 7.0km[202o] CW.