Answer:
Magnitude of fourth displacement is approximately 95 metres,
Direction of fourth displacement is straight west.
Answer:
System D --> System C --> System A --> System B
Explanation:
The gravitational force between two masses m1, m2 separated by a distance r is given by:
where G is the gravitational constant. Let's apply this formula to each case now to calculate the relative force for each system:
System A has masses m and m separated by a distance r:
system B has masses m and 2m separated by a distance 2r:
system C has masses 2m and 3m separated by a distance 2r:
system D has masses 4m and 5m separated by a distance 3r:
Now, by looking at the 4 different forces, we can rank them from the greatest to the smallest force, and we find:
System D --> System C --> System A --> System B
Answer:
82.4 cm
Explanation:
The object and screen are kept fixed ie the distance between them is fixed and by displacing lens between them images are formed on the screen . In the first case let u be the object distance and v be the image distance
then ,
u + v = 184 cm
In the second case of image formation , v becomes u and u becomes v only then image formation in the second case is possible.
The difference between two object distance ie( v - u ) is the distance by which lens is moved so
v - u = 82.4 cm
Answer:
<em>Installing interpoles in armature core helps to cut down the spark in DC generators. </em>
Explanation:
A dc generator has a split ring type commutator to convert ac current generated to dc. The commutator comes in contact with the brushes throughout the working of the generator. Sparks occur in this region of contact.
When current flows through the armature coil it produces armature flux which opposes the main flux. This is called armature reaction and is the reason for sparks.
Interpol's are small auxiliary poles placed between the main poles of the generator. They are wound by wires of a number of turns connected in series with the armature. Interpol's produce a field that cancels the magnetising field of the armature and thus cancels armature reaction.