Answer:
0.81 m/s^2
Explanation:
A child rides a bicycle from rest
The child reaches a velocity of 3.8m/s
The time is 4.7 secs
Therefore the acceleration can be calculated as follows
v= u + at
3.8= 0 + a(4.7)
3.8= 0 + 4.7a
3.8-0= 4.7a
3.8= 4.7a
a= 3.8/4.7
= 0.81 m/s^2
Hence the acceleration is 0.81 m/s^2
Answer:
F = 1.07 x 10⁻⁷ N
Explanation:
The gravitational force of attraction between two objects can be found by the use of Newton's Gravitational Law:
where,
F = Gravitational Force of attraction = ?
G = Universal Gravitational Constant = 6.67 x 10⁻¹¹ N.m²/kg²
m₁ = m₂ = mass of spheres = 20 kg
r = distance between the objects = 50 cm = 0.5 m
Therefore,
<u>F = 1.07 x 10⁻⁷ N</u>
Answer: Option (B) is the correct answer.
Explanation:
In a solid, molecules are held together by strong intermolecular forces of attraction. As a result, they are unable to move from their initial place but they can vibrate at their mean position.
Hence, in solid substances the molecules have low kinetic energy.
Whereas in liquids, the molecules are held by less strong intermolecular forces of attraction as compared to solids. Due to which they are able to slide past each other. Hence, they have medium kinetic energy.
In gases, the molecules are held by weak Vander waal forces. Hence, they have high kinetic energy due to which they move rapidly from one place to another leading to more number of collisions.
Hence, gases are able to expand more rapidly as compared to liquids.
Thus, we can conclude that out of the given options solid = low; liquid = medium; gas = high, combination of the state of matter and the corresponding dryer speed is correct.
Answer:
The Earth's surfaces changes in slow processes, erosion and weathering, and some changes are due to rapid processes, such as: landslides, volcanic eruptions, tsunamis and earthquakes.
Explanation:
Answer:
0.52°
Explanation:
refractive index for blue light, nb = 1.640
Refractive index for red light, nr = 1.595
Angle of incidence, i = 30°
Let the angle of refraction for blue light is rb and the angle of refraction for red light is rR.
By use of Snell's law for blue light
By use of Snell's law for red light
The angle between the two beams, 
θ = 18.27° - 17.75°
θ = 0.52°
