Answer:
This difference is kept to a minimum because the resistance in transformers is a few tens of ohms and the resistance of modern voltmeters is of the order of MΩ.
Explanation:
A voltmeter is built by a galvanometer and a resistance in series, this set is connected in parallel to the resistance where the voltage is to be measured, therefore the voltage is divided between the voltmeter and the element to be measured, consequently the measured voltage It is less than the calculated one, since for them the resistance of the voltmeter is assumed infinite.
This difference is kept to a minimum because the resistance in transformers is a few tens of ohms and the resistance of modern voltmeters is of the order of MΩ.
Gases can be compressed, because they just take up the space surrounding them. The attractive forces between the particles in a gas are very weak, so the particles are free to move in random direction. They just move along until they collide, either with the walls of the container or with each other. Moreover, gases can be compressed because the particles are far apart and they have space to move into.
Answer:
d.Energy as heat transferred into an object is determined by the amount of work done on the object.
Explanation:
Answer:
7.2g
Explanation:
From the expression of latent heat of steam, we have
Heat supplied by steam = Heat gain water + Heat gain by calorimeter
mathematically,
+
=
+
L=specific latent heat of water(steam)=2268J/g
=specific heat capacity=4.2J/gK
=specific heat capacity of calorimeter =0.9J/gk
=280g
=38g
α=change in temperature
=(40-25)=15
=(40-25)=15
=(100-40)=60
Note: the temperature of the calorimeter is the temperature of it content.
From the equation, we can make
the subject of formula

Hence

Hence the amount of steam needed is 7.2g
Answer:
The mutual speed immediately after the touchdown-saving tackle is 4.80 m/s
Explanation:
Given that,
Mass of halfback = 98 kg
Speed of halfback= 4.2 m/s
Mass of corner back = 85 kg
Speed of corner back = 5.5 m/s
We need to calculate their mutual speed immediately after the touchdown-saving tackle
Using conservation of momentum

Where,
= mass of halfback
=mass of corner back
= velocity of halfback
= velocity of corner back
Put the value into the formula



Hence, The mutual speed immediately after the touchdown-saving tackle is 4.80 m/s