Answer:
-8.4°C
Explanation:
From the principle of heat capacity.
The heat sustain by an object is given as;
H = m× c× (T2-T1)
Where H is heat transferred
m is mass of substance
T2-T1 is the temperature change from starting to final temperature T2.
c- is the specific heat capacity of ice .
Note : specific heat capacity is an intrinsic capacity of a substance which is the energy substained on a unit mass of a substance on a unit temperature change.
Hence ; 35= 1× c× ( T2-(-25))
35= c× ( T2+25)
35 =2.108×( T2+25)
( T2+25)= 35/2.108= 16.60°{ approximated to 2 decimal place}
T2= 16.60-25= -8.40°C
C, specific heat capacity of ice is =2.108 kJ/kgK{you can google that}
Question:
A wire 2.80 m in length carries a current of 5.20 A in a region where a uniform magnetic field has a magnitude of 0.430 T. Calculate the magnitude of the magnetic force on the wire assuming the following angles between the magnetic field and the current.
(a)60 (b)90 (c)120
Answer:
(a)5.42 N (b)6.26 N (c)5.42 N
Explanation:
From the question
Length of wire (L) = 2.80 m
Current in wire (I) = 5.20 A
Magnetic field (B) = 0.430 T
Angle are different in each part.
The magnetic force is given by

So from data

Now sub parts
(a)

(b)

(c)

Part a)
per day electricity power consumed when 100 W bulb is used for 8 hours

for one year consumption

now the cost will be given

now when other energy efficient light is used

for one year consumption

now the cost will be given

Explanation:
It is given that,
Mass of the tackler, m₁ = 120 kg
Velocity of tackler, u₁ = 3 m/s
Mass, m₂ = 91 kg
Velocity, u₂ = -7.5 m/s
We need to find the mutual velocity immediately the collision. It is the case of inelastic collision such that,


v = -1.5 m/s
Hence, their mutual velocity after the collision is 1.5 m/s and it is moving in the same direction as the halfback was moving initially. Hence, this is the required solution.
The image is always virtual and erect. The image is highly diminished or point sized. It is always formed between F and P.