Answer:
9 kilojoules of energy are stored in a kilogram of concrete due to sensible heat.
Explanation:
In this exercise we need to determined the sensible heat store in a kilogram of concrete due to a change in temperature. Sensible heat (
), measured in kilojoules, is defined by the following expression:
(1)
Where:
- Mass, measured in kilograms.
- Average specific heat of concrete, measured in kilojoules per kilogram-degree Celsius.
, 
- Initial and final temperatures of concrete, measured in degrees Celsius.
If we know that 
, 
, 
and 
, then the energy store in a kilogram of concrete is:
9 kilojoules of energy are stored in a kilogram of concrete due to sensible heat.
Throw it sideways and try to make it spin around but it needs to be thrown high up then it should kinda glide down
Answer:
option A
Explanation:
given,
For exerted by the worker = 245 N
angle made with horizontal = 55°
we need to calculate Force which is not used to move the crate = ?
Movement of crate is due to the horizontal component of the force.
Crate will not move due to vertical force acting on the it.
hence, worker's force not used to move the crate is equal to 200.69
The correct answer is option A
Answer:
D. is always perpendicular to the surface of the conductor
Explanation:
1) Answer is (D) option. Electric field just outside surface of charged conductor is normal to conductor at that point.
It can be explained on the basis of the fact that, Electric field inside conductor under static condition is zero. As a result potential difference between any two points with in conductor is zero. So whole of conductor is equipotential body.
Equipotential surface and Electric field lines always cut at 90 degrees to each other. Conductor being equipotential body, Electric field lines starting or terminating at conductor must be normal to surface. Hence electric field just outside conductor is perpendicular or normal to surface.
