Question

What does I,j denotes ………..
column
unit vector
scalar
matrix
2 Represesnt the given velocity 230km/h in the direction
2000
7cm
5cm
14cm
10cm
3 A negative vector could be denoted as ……….
w,w
a,b
u,v
u,-u
4 The sum of a vector and the negative of another vector could be written as …………
w+w
w+(-w)
w
None of the above
5What type of vector is w+(-w)=0
null vector
scalar vector
vector
magnitude

Answer 1

Answer on Question # 52233 – Math – Vector Calculus

1. What does $i,j$ denotes ...

a. column

b. unit vector

c. scalar

d. matrix

Answer: b. unit vector

2. Represents the given velocity $230\,\mathrm{km/h}$ in the direction $200{}^{\circ}$

a. $7\,\mathrm{cm}$

b. $5\,\mathrm{cm}$

c. $14\,\mathrm{cm}$

d. $10\,\mathrm{cm}$

Answer: None of the above

We should find coordinates $(v_x, v_y)$ of its end. By definition $v_x = v \cos \alpha$, $v_y = v \sin \alpha$.

Substituting values we get $v_x = v \cos \alpha = 230 \cdot \cos 200{}^\circ = 230 \cdot (-0.93969) = -216.13\,\mathrm{km/h} = -216.13 \cdot 1000\,\mathrm{m/(3600\,s)} = -60.04\,\mathrm{m/s}$,

$v_y = v \sin \alpha = 230 \cdot \sin 200{}^\circ = 230 \cdot (-0.34202) = -78.665\,\mathrm{km/h} = -78.665 \cdot 1000\,\mathrm{m/(3600\,s)} = -21.85\,\mathrm{m/s}$.

Thus, $v = (-216.13\,\mathrm{km/h}, -78.665\,\mathrm{km/h})$.

3. A negative vector could be denoted as ...

a. w, w

b. a, b

c. u, v

d. u, -u

Answer: d. u, -u

4. The sum of a vector and the negative of another vector could be written as ...

a. w + w

b. w + (-w)

c. w

d. None of the above

Answer: d. None of the above

5. What type of vector is $w + (-w) = 0$

a. null vector

b. scalar vector

c. vector

d. magnitude

Answer: a. null vector

www.AssignmentExpert.com