48J
Explanation:
Given parameters:
Weight of the book = 16N
Height of the shelf = 3m
Unknown:
Work done to raise the book = ?
Solution:
Work done is defined as the product of force and distance. The force here is the weight of the book which signifies that it was carried in the vicinity of gravitational force.
Work done = Force x distance = weight x distance
Weight is a type of force;
Input the parameters;
Work done = 16 x 3 = 48J
The unit of workdone is in Joules
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Work done brainly.com/question/9100769
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Answer:
magnitude = 3
unit vector = 
Explanation:
Given vectors:
u = 2i + 2j - k
v = -i + k = -i + 0j + k
(a) u x v is the cross product of u and v, and is given by;
u x v = i(2+0) - j(2 - 1) + k(0 - 2)
u x v = 2i - j - 2k
Now the magnitude of u x v is calculated as follows:
| u x v | = 
| u x v | = 
| u x v | = 
| u x v | = 3
Therefore, the magnitude of u x v is 3
(b) The unit vector û parallel to u x v in the direction of u x v is given by the ratio of u x v and the magnitude of u x v. i.e
û =
u x v = 2i - j - 2k [<em>calculated in (a) above</em>]
|u x v| = 3 [<em>calculated in (a) above</em>]
∴ û = 
∴ û = 
The law of conservation of energy states that energy is neither created nor destroyed; the amount remains constant. For example, a form of energy-thermal energy, or heat, occurs by convection or conduction
Answer:
Option 4
Explanation:
During heating actually heat transfer takes place from a body at higher temperature to a body at lower temperature and the heat transfer takes place until both attain the same temperature
Therefore heat transfer depends on the temperature of the systems
Now while comparing the thermal energies of the systems, if both the systems have same mass then the system which is at higher temperature has greater thermal energy when compared to the system which is at lower temperature
So in this case assuming that both the systems have same mass then the energy will leave the system with greater thermal energy and go into the system with less thermal energy as the system with greater thermal energy in this case will be at higher temperature and we are considering this assumption because thermal energy not only depends on temperature but also depends on mass of the system