Answer:
42
Explanation:
27.9+13+1.21=42.11
to a significant figure= 42
Answer:
Magnitude of displacement = 2.07 km
Magnitude of average velocity = 1.17 kmph
Explanation:
Let east represent positive x axis and north represent positive y axis.
A bird watcher meanders through the woods, walking 1.93 km due east, 1.03 km due south, and 3.84 km in a direction 52.8 ° north of west.
1.93 km due wast
s ₁ = 1.93 i km
1.03 km due south
s₂ = -1.03 j km
3.84 km in a direction 52.8 ° north of west
s₃ = -3.84 cos 52.8 i + 3.84 sin 52.8 j = -2.32 i + 3.06 j km
Total displacement
s = s ₁+ s₂+ s₃ = 1.93 i - 1.03 j -2.32 i + 3.06 j = -0.39 i + 2.03 j
Magnitude of displacement,
Time taken = 1.771 hour
Magnitude of average velocity,
You have done 43.9 joules of work to lift the can.
Answer:
Redshift, or lower power
Explanation:
doppler effect
waves get stretched when you are moving away from something, and squished when you are moving towards it. Imagine you have a long, bent wire. if you stretch out the wire, the wavelength becomes longer. This also applies to sound.
Answer:
Explanation:
Let λ be the required wavelength.
Two fringe patterns will be formed on the screen which will overlap each other. Let 9 th bright fringe of first coincides with 11 th bright fringe of second.
position of 9 the bright fringe of first = 9x 646 x D/d nm
position of 11 th bright fringe of second pattern = 11 x λ x D/d
now , 9 x 646 = 11 x λ
λ = 9 x 646 / 11 = 528.54 nm.