Answer:
B) 40 km West
Explanation:
Let position of B is origin so with respect of City B the position of A is given as
south of city B
now Bus starts from City A and travels a distance of 50 km at 37 degree North of East to reach city C
so it is
![r_{CA} = 50(cos37\hat i + sin37 \hat j)](https://tex.z-dn.net/?f=r_%7BCA%7D%20%3D%2050%28cos37%5Chat%20i%20%2B%20sin37%20%5Chat%20j%29)
![r_{CA} = 40\hat i + 30\hat j](https://tex.z-dn.net/?f=r_%7BCA%7D%20%3D%2040%5Chat%20i%20%2B%2030%5Chat%20j)
now the position of C is given with respect to A
in order to find the position of C with respect to B we can say
![r_C = r_{CA} + r_A](https://tex.z-dn.net/?f=r_C%20%3D%20r_%7BCA%7D%20%2B%20r_A)
![r_C = 40\hat i + 30\hat j + (-30 \hat j)](https://tex.z-dn.net/?f=r_C%20%3D%2040%5Chat%20i%20%2B%2030%5Chat%20j%20%2B%20%28-30%20%5Chat%20j%29)
![r_C = 40 \hat i](https://tex.z-dn.net/?f=r_C%20%3D%2040%20%5Chat%20i)
so in order to reach at city B from city C bus has to travel 40 km towards West
TRUE
They propagate perpendicular to each other in the case of an Electromagnetic waves....
Both can be seen in the case of a moving charge
Hope this helps!
Given:
rod of circular cross section is subjected to uniaxial tension.
Length, L=1500 mm
radius, r = 10 mm
E=2*10^5 N/mm^2
Force, F=20 kN = 20,000 N
[note: newton (unit) in abbreviation is written in upper case, as in N ]
From given above, area of cross section = π r^2 = 100 π =314 mm^2
(i) Stress,
σ
=force/area
= 20000 N / 314 mm^2
= 6366.2 N/mm^2
= 6370 N/mm^2 (to 3 significant figures)
(ii) Strain
ε
= ratio of extension / original length
= σ / E
= 6366.2 /(2*10^5)
= 0.03183
= 0.0318 (to three significant figures)
(iii) elongation
= ε * L
= 0.03183*1500 mm
= 47.746 mm
= 47.7 mm (to three significant figures)
Answer:
The number of crates is 84580.
Explanation:
mass, m = 30 kg
height, h = 0.9 mm
Power, P = 0.5 hp = 0.5 x 746 W = 373 W
time, t = 1 minute = 60 s
Let the number of crates is n.
Power is given by the rate of doing work.
![P = \frac{n m gh}{t}\\\373 =\frac{n\times 30\times9.8\times 0.9\times 10^{-3}}{60}\\\\n =84580](https://tex.z-dn.net/?f=P%20%3D%20%5Cfrac%7Bn%20m%20gh%7D%7Bt%7D%5C%5C%5C373%20%3D%5Cfrac%7Bn%5Ctimes%2030%5Ctimes9.8%5Ctimes%200.9%5Ctimes%2010%5E%7B-3%7D%7D%7B60%7D%5C%5C%5C%5Cn%20%3D84580)
Answer: i could prolly answer if it made more sense. which of the following where?