The correct option is C) The angle between the vectors is 120°.
Why?
We can solve the problem and find the correct option using the Law of Cosine.
Let A and B, the given two sides and R the resultant (sum),
Then,
So, using the law of cosines, we have:
Hence, we have that the angle between the vectors is 120°. The correct option is C) The angle between the vectors is 120°
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Answer:
4 m/
Explanation:
From Equilibrium of forces, The Tension in string is cancelled by the Weight (product of mass and acceleration due to gravity) of the body acting downwards.
The Net force = Mass * Acceleration.
Since Net Force = 20 Newton, Mass = 5kg, therefore;
20 = 5kg * acceleration. Dividing the RHS and LHS of the equation by 5, we have;
Acceleration = 
which gives 4.
Note: RHS means Right Hand Side.
LHS means Left Hand Side.
Explanation:
<em>The height of the pendulum is measured from the lowest point it reaches (point 3). </em>
At 1, the kinetic energy of the pendulum is zero (because it is not moving), and it has maximum potential energy.
At 2, the pendulum has both kinetic and potential energy, and how much of each it has depends on its height—smaller the height greater the kinetic energy and lower the potential energy.
At 3, the height is zero; therefore, the pendulum has no potential energy, and has maximum kinetic energy.
At 4, the pendulum again gains potential energy as it climbs back up, Again how much of each forms of energy it has depends on its height.
At 5, the maximum height is reached again; therefore, the pendulum has maximum potential energy and no kinetic energy.
Hope this helps :)
Answer:
Total energy is constant
Explanation:
The laws of thermodynamics state that thermal energy (heat) is always transferred from a hot body (higher temperature) to a cold body (lower temperature).
This is because in a hot body, the molecules on average have more kinetic energy (they move faster), so by colliding with the molecules of the cold body, they transfer part of their energy to them. So, the temperature of the hot body decreases, while the temperature of the cold body increases.
This process ends when the two bodies reach the same temperature: we talk about thermal equilibrium.
In this problem therefore, this means that the thermal energy is transferred from the hot water to the cold water.
However, the law of conservation of energy states that the total energy of an isolated system is constant: therefore here, if we consider the hot water + cold water as an isolated system (no exchange of energy with the surroundings), this means that their total energy remains constant.
To stop the car it would be 100m because if the car is going to 65km/h then it would still be 100km/h
