-- First, we have to decide how to handle the two resistors.
The effective resistance of resistors in series is the sum
of their individual resistances. That is, they act like a single
resistor, whose resistance is the sum of all of them.
So in this question, the 4.0 ohms and the 7.5 ohms act like a
single resistor of 11.5 ohms.
-- The current in the circuit is
(the supply voltage) / (the total resistance)
= (9.0 volts) / (11.5 ohms)
= 0.783... Ampere (rounded)
Answer:
there is the increase the temperature of cold body and decrease the temperature of hot body
Answer:
a) 
b) x = 4.47 cm
c) 
d) x = 1.48 cm
Explanation:
a) The center of mass is equal to:

Where m is the mass of beads and x is the distances, if x₁ = d₁, x₂ = d₂ and x₃ = d₃

b) If
m₁ = 23g
m₂ = 15 g
m₃ = 58 g
d₁ = 1.1 cm
d₂ = 1.9 cm
d₃ = 3.2 cm

c) The center of the mass of the beads realtive to the center of bead is:

d) 
Answer:
Upthrust = 20 N
Explanation:
The question says that "A body weighs 100N in air and 80N when submerged in water. Calculate the upthrust acting on the body
?"
Upthrust is defined as the force when a body is submerged in liquid, then liquid applies a force on it.
ATQ,
Weight of body in air is 100 N
Weight of body in water is 80 N
Upthrust is equal to the weight of body in air minus weight of body in water.
Upthrust = 100 N - 80 N
Upthrust = 20 N
So, 20 N of upthrust is acting on the body.