I'm assuming the question is what is the robin's speed relative to to the ground...
Create an equation that describes its relative motion.
rVg = rVa + aVg
Substitute values.
rVg = 12 m/s [N] + 6.8 m/s [E]
Use vector addition.
| rVg | = √ | rVa |² + | aVg |²
| rVg | = √ 144 m²/s² + 46.24 m²/s²
| rVg | = √ 19<u>0</u>.24 m²/s²
| rVg | = 1<u>3</u>.78 m/s
Find direction.
tanФ = aVg / rVa
tanФ = 6.8 m/s / 12 m/s
Ф = 29°
Therefore, the velocity of the robin relative to the ground is 14 m/s [N29°E]
Answer:
Explanation:
mass, m = 1400 kg
height, h = 16 m
initial velocity, u = 21 m/s
final velocity, v = 13 m/s
Work done by engine, We = 80 kJ
Let the work done by the friction force is Wf.
Use the work energy theorem
net work done = change in kinetic energy
work done by engine + work done by friction force + work done by the gravitational force = Change in kinetic energy
80000 + Wf - m x g x h = 0.5 m ( v² - u²)
80000 + Wf - 1400 x 9.8 x 16 = 0.5 x 1400 x ( 169 - 441 )
- 139520 + Wf = - 190400
Wf = 50880 J
<span>energy is directly proportional fo frequency
as in blue photons are more energetic than red photons
so
E = h * f
look up h (Planck's constant)
plug and play!</span><span>
</span>
<em>The acceleration of both the rocks is only due to the gravitational force acting on them. Even though the speed of thrown rock would be greater than that of dropped rock, the acceleration of both the rocks would be g downwards.</em>
