# Civil Engineering - Applied Mechanics - Discussion

### Discussion :: Applied Mechanics - Section 1 (Q.No.3)

3.

At a given instant ship A is travelling at 6 km/h due east and ship B is travelling at 8 km/h due north. The velocity of B relative to A is

 [A]. 7 km/hrs [B]. 2 km/hrs [C]. 1 km/hrs [D]. 10 km/hrs [E]. 14 km/hrs.

Explanation:

No answer description available for this question.

 Gaurav Gupta said: (Apr 26, 2013) By using pythagoras theorem; (8*8) + (6*6) equal to 100 and square root of 100 is 10.

 Saurabh said: (Jul 22, 2013) It should be 10. Why it is 14 anyone explain this?

 Ankur Padalia said: (Dec 2, 2013) Using the pythagoras theorem.

 Amol Ashok Lande said: (Feb 6, 2014) (V)x = 6. (V)y = 8. Vb/a = (36+64)^1/2. Vb/a = 10 km/hr.

 Saleem Khan said: (Apr 21, 2014) Both force are acting on right angle so we will find resultant acc to parallelogram law. R^2 = f1^2 + f2^2 + cos90. But there is value of cos90 = 0.

 Abdul Salam Ansari said: (Feb 6, 2015) Both force are acting on right angle so, we will find resultant according to parallelogram law. R^2 = f1^2 + f2^2 +2f1*f2*cos90. But there is value of cos90 = 0. We know, f1 = 6km/hr and f2 = 8km/hr. R^2 = 6^2+8^2+2*6*8*0. => R^2 = 36+64. => R = (100)^1/2. => R = 10km/hr.

 Chandan Kumar said: (Feb 16, 2015) The force are acting at right angle so simply you know that find resultant r^2 = p^2+Q^2. Assume p = 6, q = 8 substitute this values. r^2 = 6^2+8^2. r^2 = 36+64. r^2 = 100. Now do the square root of 100 is 10. Thus r = 10km/hr.

 A Kumar said: (Jul 25, 2015) Va = 6i+0j, Vb = 0i+8j. Vba = Vb-Va. 6i+0j-(0i+8j) = 6i-8j. Magnitude of Vba = (6^2+8^2)^1/2. = (100)^1/2. = 10 mtr/sec.

 Usama Ahmad said: (Aug 19, 2015) 6*6+8*8=100 s of 100=10.

 Nitesh Jayswal said: (Dec 15, 2016) By using Pythagoras theorem:- 8 * 8 + 6 * 6 = 100. Square root of 100 = 10km/hr.

 Kuldeep Singh Umath said: (Jan 8, 2017) It should be 10. I agree.

 Jitendra Singh said: (Jan 14, 2017) Va = 6i+0j, Vb = 0i + 8j. Vba = Vb - Va. 6i + 0j - (0i + 8j) = 6i - 8j. Magnitude of Vba = (6^2+8^2)^1/2. = (100)^1/2. = 10 mtr/sec.

 Biki said: (Jun 3, 2017) The Answer is correct. Then velocity of A relative to B is what? Is it also 10km/h?

 Kirthi said: (Jul 16, 2017) I am not getting How it's 10? please explain.

 Amandeep Yadav said: (Sep 8, 2017) 6+(8/2)=6+4 = 10km/hr.

 Mohbat Baloch said: (Sep 10, 2017) By using Pythagoras theorem it is 10.

 Prashant said: (Mar 12, 2018) But how we can say 10km/h is the velocity relative to A?

 Alok Kumar Singh said: (Feb 19, 2019) I am not getting this, please Exlain in deeply.

 Prem K said: (Jun 4, 2019) Efx = 6. Efy = 8. Resultant R= {sqr(Efx)+sqr(Efy)}1/2. R = (36+64)'1/2. R = (100)'1/2 = 10.

 Larry L said: (Nov 6, 2019) Va = 6kmph. Vb = 8kmph. Vba = Vb+Va(Since they are of different dir.). = 8+6. = 14kmph.