Answer
given,
given,
small cube side = 10 cm
larger cube side = 12 cm
density of steel = 7 g/cm³
density of aluminium = 2.7 g/cm³
density of the water (ρ₁)= 1 g/cm³
Cube A and B made of steel
buoyant force of Cube A
B₁ = ρ₁ V g = 1 x 10 x 10 x 10 x g= 1000 g
for cube B
B₂ = ρ₁ V g = 1 x 12 x 12 x 12 x g= 1728 g
buoyant force of Cube C
B₃ = ρ₁ V g = 1 x 10 x 10 x 10 x g= 1000 g
for cube D
B₄ = ρ₁ V g = 1 x 12 x 12 x 12 x g= 1728 g
buoyant force acting on the cube depends on the density of the fluid
hence,
B₂ = B₄ > B₁ = B₃
Answer:
Assuming it starts at 72 kmph and hits a dead stop: Divide 72 by 60 for distance per minute. So, 1.2km per minute. 1.2km is 1200m and 4 seconds is one fifteenth of a minute.
Explanation:
Answer:
90 meters
Explanation:
Given:
x₀ = 0 m
v₀ = 0 m/s
v = 30 m/s
t = 6 s
Find:
x
x = x₀ + ½ (v + v₀)t
x = 0 + ½ (30 + 0)(6)
x = 90
The car travels 90 meters.
Answer:
Explanation:
Given
Force 
one at an angle of
East of North and another at
West of North
Net Force is in North Direction

Forces in horizontal direction will cancel out each other
thus Work done will be by north direction forces

here 

Explanation :
When an electron jumps from one energy level to another, the energy of atom gets changed.
If a photon gets absorbed, the electron will move to higher energy levels and then fall back to the lower energy levels. Then each time a photon will be absorbed whose energy is given by difference between the initial and final energy levels i.e
In Balmer series, the transition is from higher energy levels to n = 2.
So, the necessary condition for Balmer series is that the electron should be at first excited state or n = 2 level as shown in figure.