Wood is a bad conductor of heat. The drilling process involve heat generation between the drill and the wooden material that can not be dissipated away easily. With deep drilling the drill may get so hot that the chips come out in a state of smoking coal.<span>
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Answer: Option (b) is the correct answer.
Explanation:
Stress is a situation in which our mind or body feel the pressure from our surroundings, ideas or thoughts. Stress causes distress in the body and mind of an individual.
For example, Ria has not done her homework and she is worried what punishment might her teacher give her when she get to know this.
When can get relive from stress by talking about our thoughts or worries with an individual. The other person might help us solve our problems or he might suggest us in a better way.
Therefore, we can conclude that Maria best manage this stress by talking to family, friends, and teachers for support.
Answer: -3.49 m/s (to the south)
Explanation:
This problem can be solved by the Conservation of Momentum principle which establishes the initial momentum
must be equal to the final momentum
, and taking into account this is aninelastic collision:
Before the collision:
(1)
After the collision:
(2)
Where:
is the mass of the car
is the velocity of the car, directed to the north
is the mass of the truck
is the velocity of the truck, directed to the south
is the final velocity of both the car and the truck
(3)
(4)
Isolating
:
(5)
(6)
Finally:
The negative sign indicates the direction of the velocity is to the south
Given:
(Initial velocity)u=20 m/s
At the maximum height the final velocity of the ball is 0.
Also since it is a free falling object the acceleration acting on the ball is due to gravity g.
Thus a=- 9.8 m/s^2
Now consider the equation
v^2-u^2= 2as
Where v is the final velocity which is measured in m/s
Where u is the initial velocity which is measured in m/s
a is the acceleration due to gravity measured in m/s^2
s is the displacement of the ball in this case it is the maximum height attained by the ball which is measured in m.
Substituting the given values in the above formula we get
0-(20x20)= 2 x- 9.8 x s
s= 400/19.6= 20.41m
Thus the maximum height attained is 20.41 m by the ball