Answer:
16km/h
Explanation:
Vt=20km/h ---train speed
Vd=4km/h
Donas speed relative to ground is:
Vrd=Vt-Vd
Donas is moving in opposite direction of train .
Vrd=20km/h-4km/h
Vrd=16km/h
The speed of the large fish after eating the small fish is 4.76 m/s.
We can apply the law of momentum conservation to calculate the speed of the large fish.
Let the velocity of the large fish after eating small fish is v.
According to law of momentum conservation
m1u1+m2u2=(m1+m2)v
here, m1 is the mass of the large fish, u1 is the initial speed of larger fish, ml is the mass of the small fish, u2 is the initial speed of small fish
10*5+0.5*0=(10+0.5)v
v=4.76 m/s
Answer:
113.53 g
Explanation:
Please see attached photo for explanation.
In the attached photo, M is the mass of the meter stick.
The value of M can be obtained as shown below:
Clockwise moment = M × 10.5
Anticlockwise moment = 65.5 × 18.2
Anticlockwise moment = Clockwise moment
65.5 × 18.2 = M × 10.5
1192.1 = M × 10.5
Divide both side by 10.5
M = 1192.1 / 10.5
M = 113.53 g
Thus, the mass of the meter stick is 113.53 g
Answer:
655 nm
Explanation:
When the intereference is destructive then the thickness, d of antireflective film coating one side is given by
2d=w/2n
Where w is wavelength and n is the reflective index of the film
Making w the subject of formula then
w=4nd
Substituting 1.25 for n and 131 nm for d then the wavelength will be
w=4*1.25*131=655 nm
Therefore, the wavelength is equivalent to 655 nm
Answer:
momentum= mass x velocity
= 11 x 1200 =13200kgm/s