Question

Solve it!

#No spams
#No Google

Answer with Well - explained solution !​

Answer 1

Ball A :

• mass of ball A= 12 g
• volume of ball A = 15 cm ³

we know that ,

density = mass / volume

density = 12 /15

density = 4/5 = 0.8 g / cm³

Since ,

density of ball A < density of water

0.8 < 1

hence the ball will float

For a floating body ,

Upthrust = mg

Upthrust = 12×10

Upthrust = 120 N

Ball B :

• mass of Ball B = 12 g
• density of ball B = 8 g / cm³

we know that ,

density = mass / volume

volume = mass / density

volume = 12 /8

volume = 3 / 2 cm³

volume of ball B = volume of water displaced = 3/2 cm³

we know that ,

upthrust acting on the ball

= volume of water displaced × density of water × g

= 3/2 ×1×10

= 15 N

As the upthrust acting in ball B is less than the weight of the ball it will sink

Answer 2

★ᏀᏆᏙᎬΝ:-

• Ball A's mass → 12g
• Ball B's mass → 12g
• Iron's Density → $\sf 8.0 \ g \ cm^{-3}$
• Volume of ball A → 15 cm³
• Volume of ball B → M÷D = 12÷8 = $\sf 1.5 \ cm^{-3}$

★To find:-

• Upthrust on each ball.
• Ball which will sink.

★Solution:-

1. Upthrust on each ball.

$\sf Upthrust \ on \ ball \ A = Volume \ of \ ball \ A \times density \ of \ water \times g$

$\implies \bf 15 \times 1 \times g= 15gf$

$\bullet\qquad\qquad\boxed{\bf Upthrust \ on \ Ball \ A =15gf}$

$\sf Upthrust \ on \ ball \ B= Volume \ of \ ball \ B \times density \ of \ water \times g$

$\implies \bf 1.5 \times 1 \times g= 1.5gf$

$\bullet\qquad\qquad\boxed{\bf Upthrust \ on \ Ball \ B =1.5gf}$

• 2.) Ball which will sink

Ball B will sink.

Reason why?

Upthrust on ball B is 1.5 gf which is less than its weight 12 gf, while upthrust on ball A will be 15gf if it is fully submerged, which is greater than its weight 12gf, so it will float with its submerged part for which the upthrust becomes equal to its weight which is 12gf.

Hope it helps!