1.
Answer:
Part a)

Part b)

Explanation:
Part a)
Length of the rod is 1.60 m
diameter = 0.550 cm
now if the current in the ammeter is given as

V = 17.0 volts
now we will have


R = 0.91 ohm
now we know that



Part b)
Now at higher temperature we have


R = 0.98 ohm
now we know that



so we will have



2.
Answer:
Part a)

Part b)

Explanation:
Part a)
As we know that current density is defined as

now we have

Now we have


so we will have

Part b)
now we have

so we have


so we have


Answer: Option B
Explanation : When a negatively charged object A gets in contact with the neutral object B, the negative charge of object will induce the opposite charges on object B. Hence, there will be a positive charge on object B
Answer:
E. 3h
Explanation:
We know that
u = 0 m/s.
velocity after t = 1s
v = u+gt = 0+9.81 x 1s= 9.81 m/s
distance covered in 1st sec
= =>> ut+0.5 x g x t²
=>>0 + 0.5x 9.81 x 1 = 4.90m
Let 4.90 be h
distance travelled in 2nd second will now be used
So velocity after t = 1s
=>>1 x t+ 0.5 x g x t²
=>9.81x 1 + 0.5 x 9.81 x 1 = 3 x 4.90
So since h= 4.90
Then the ans is 3x h = 3h
Answer:
a. Power = 1000 Watts or 1 Kilowatts.
b. Current = 4 Amperes.
Explanation:
Given the following data;
Energy consumed = 1.8MJ = 1.8 × 10^6 = 1800000 Joules
Voltage = 250V
Time = 30 minutes to seconds = 30 * 60 = 1800 seconds
To find the power rating;
Power = energy/time
Substituting into the equation, we have;
Power = 1800000/1800
Power = 1000 Watts or 1 Kilowatts.
b. To find the current taken from the supply;
Power = current * voltage
1000 = current * 250
Current = 1000/250
Current = 4 Amperes.
Answer:
32.176 ft/s²
9.807 m/s²
Explanation:
Data provided in the question:
Acceleration of the free falling object = 78979.4 mi/hr²
a) In ft/s
Now,
1 mi = 5280 foot
and,
1 hour = 3600 seconds
thus,
78979.4 mi/hr = 
or
78979.4 mi/hr = 32.176 ft/s² ...............(1)
b) In m/s²
Now,
1 foot = 0.3048 m
thus,
we have from 1
32.17 ft/s² = 
or
78979.4 mi/hr = 32.176 ft/s² = 9.807 m/s²