Answer:
The car is decelerating and its acceleration is negative.
Explanation:
First thing to consider. The car traveling direction is not important to answer the question.
Second, there are two affirmations on each sentence. So, lets take definitions:
Deceleration: Reducing the acceleration, from one value to another. No matter if the acceleration for the moment is positive or negative.
Acceleration negative: the driver is applying a force to make speed=0, the sign of this force must negative in order for the car to stop, other way it will go faster. Acceleration is the change rate of speed, if the speed is going down, the total acceleration until cars stops must be negative.
Answer:
The K.E is maximum when the child is at the vertical position and the P.E is maximum at the extreme deviated position from the vertical.
Explanation:
- A child is swinging on swing up and down has both kinetic and potential energy.
- The total mechanical energy of the system is conserved throughout the system. At any instant the total mechanical energy is given by,
E = K.E + P.E
- The K.E is maximum when the child is at the vertical position.
- The P.E is maximum at the extreme deviated position from the vertical.
- And when K.E is maximum P.E becomes minimum and vice versa as per the law of conservation of energy.
Answer:Decreases
Explanation:
Given
Volume is held constant that is it is a isochoric process.
We know that
PV=nRT
as n,V& R are constant therefore only variables are
P & T
so 

As
is decreasing therefore Pressure must also decrease so that ratio remains constant.
The basic unit of energy is a joule. Kill calories measure the energy available in food.
Answer:
F = 683.8 N
Explanation:
The gravitational force of attraction between the Earth and the student is given by Newton's Law of Gravitation as follows:

where,
F = Force = ?
G = Universal gravitational constant = 6.67 x 10⁻¹¹ Nm²/kg²
m₁ = mass of Earth = 5.98 x 10²⁴ kg
m₂ = mass of student = 70 kg
r = distance between Earth and student = 6.39 x 10⁶ m
Therefore,

<u>F = 683.8 N</u>