Temperature is just a measure of how HOT or COLD a substance is, which can be easily defined by a magnitude using a numerical value say “300 K” or “27°C”. Hence we can say it is a scalar quantity.
But the energy which transfer by virtue of a temperature difference is a vector quantity, as it has both magnitude and direction of motion (from High temperature to low temperature region).
Answer: 81.619 kJ
Explanation:
Given
Mass of roller coaster is 
It reaches the steepest hill with speed of 
Hill to bottom is 51 m long with inclination of 
Height of the hill is 
Conserving energy to get kinetic energy at bottom
Energy at top=Energy at bottom

Answer:
A. The electric field points to the left because the force on a negative charge is opposite to the direction of the field.
Explanation:
The electric force exerted on a charge by an electric field is given by:
where
F is the force
q is the charge
E is the electric field
We see that if the charge is negative, q contains a negative sign, so the force F and the electric field E will have opposite signs (which means they have opposite directions). This is due to the fact that the direction of the lines of an electric field shows the direction of the electric force experienced by a positive charge in that electric field: therefore, a negative charge will experience a force into opposite direction.
Answer:
<h2>D</h2>
Explanation:
The momentum of an object can be found by using the formula
momentum = mass × velocity
From the question
mass = 2 kg
velocity/speed = 3 m/s
We have
momentum = 2 × 3 = 6
We have the final answer as
<h3>6 kg.m/s</h3>
Hope this helps you
Answer:
The door will move when the forces exerted by each individual becomes unbalanced.
Explanation:
The Door will only move when the forces exerted by each of the individual is unbalanced i.e. when the Torque is unbalanced
This is because there will only be a reaction or movement of an object when the applied force > resistant force acting on the object.
example : An object at rest will only move when the applied force is greater than the frictional forces acting on the object at rest.