Answer:
Magnetic compass
Explanation:
A magnetic field is a field that describes the magnetic effect of electric charges in a relative motion.
Magnetic field allows magnets to interact without contact. The principle involved in the function of the compass is that a magnetic field exerts a force on any moving charge and can be measured and detected by this effect.
Correct answer choice is :
C) The freezing and melting temperatures of a substance are the same.
Explanation:
Fluids have a particular temperature at which they convert into solids, identified as their freezing point. In theory, the melting point of a solid should be the same as the freezing point of the liquid. In practice, small variations among these measures can be seen. The freezing point of a matter is the same as that substance's melting point. At this distinct temperature, the substance can exist as either a solid or a liquid. At temperatures below the freezing/ melting point, the substance is a solid.
Answer:
The mass of the block, M =T/(3a +g) Kg
Explanation:
Given,
The upward acceleration of the block a = 3a
The constant force acting on the block, F₀ = Ma = 3Ma
The mass of the block, M = ?
In an Atwood's machine, the upward force of the block is given by the relation
Ma = T - Mg
M x 3a = T - Ma
3Ma + Mg = T
M = T/(3a +g) Kg
Where 'T' is the tension of the string.
Hence, the mass of the block in Atwood's machine is, M = T/(3a +g) Kg
Kinetic Energy is calculated by KE= 1/2mv2
