Answer:
The body must be moving with a constant non zero acceleration.
Explanation:
Force produces acceleration on any mass it is applied on. The acceleration produced depends on the magnitude and direction of the force. For this block being dragged by a constant horizontal force, The body will undergo a constant non-zero acceleration that will steadily increase its velocity along the direction of the force.
Answer:
a) 1450watts
b) 564watts
c) 1.11
Explanation:
Power consumed = IV
I is the current rating
V is the operating voltage
If a blow-dryer and a vacuum cleaner each operate with a voltage of 120 V and the current rating of the blow-dryer is 12 A, while that of the vacuum cleaner is 4.7 A then their individual power rating is calculated thus;
a) For blow-dryer
Operating voltage = 120V
Its current rating = 12A
Power consumed = IV
= 120×12
= 1440watts
b) For vacuum cleaner:
Operating voltage is the same as that of blow dryer = 120V
Its current rating = 4.7A
Power consumed = IV
= 120×4.7
= 564watts
c) Energy used = Power consumed × time taken
Energy used = Power × time
Energy used by blow dryer = 1440×20×60
= 1,728,000Joules
Energy used up by vacuum cleaner = 564×46×60
= 564×2760
= 1,556,640Joules
Ratio of the energy used by the blow-dryer in 20 minutes to the energy used by the vacuum cleaner in 46 minutes will be 1,728,000/1,556,640 = 1.11
420 m of total distance is covered by the skier on travelling from A to D.
Explanation:
As from the picture, it can be seen that first the skier moved from position A to position B. And the distance covered by this movement is 180 m. Then as the skier travels from position B to position C, the distance between these two positions is 140 m from the figure. As distance is a scalar quantity, the direction is not taken into consideration. So only the magnitudes of the distance between those points are added.
Now, the distance between A to B is 180 m and then from B to C is 140 m, atlast from C to D, the distance is given as 100 m.
So, the total distance will be the sum of all the above found distances. Thus, the total distance will be 180+140+100 = 420 m.
As the question is about distance, so no need to write the direction for it.
Thus, the final answer will be 420 m of total distance is covered by the skier on travelling from A to D.
Answer:
<em>There will be a huge problem of holding the wire strands together, and the power losses will also be amplified.</em>
Explanation:
The force per unit length on two current carrying conductors, lying parallel to each other is proportional to the product of the current through the conductors, and inversely proportional to their distance apart. This force is attractive if the current flows through these conductors in the same direction, and is repulsive if it flows in the opposite direction.
For the strand of wire that make up a high voltage wire bundle, there will be a force of attraction pulling the wires closer to each other, and they will experience the maximum pulling force possible, since they lie next to each other. This force helps to hold these wires in a high tension wire strand together, limiting the area, and reducing "skin effect."
In the case that this wires in the wire strand acts in opposite of the known behavior, the wires will repel and push each other apart. This pushing apart will increase power loss due "skin effect" which is increased by an increase in exposed surface area of the wire strands. This will pose a big problem for high tension transmission.
environmental control? environmental protect?
