Answer:
1.The calorie was originally defined as the amount of heat required at a pressure of 1 standard atmosphere to raise the temperature of 1 gram of water 1° Celsius. Since 1925 this calorie has been defined in terms of the joule, the definition since 1948 being that one calorie is equal to approximately 4.2 joules.
2.Boiling water at 100 degrees Celsius: 540 calories are needed to turn 1 gram (at 100 degrees Celsius) of water to steam.
When you exert a force on the coin, it will accelerate. If you push the coin and it moves at a constant velocity, the friction force must be equal to the force that you are exerting. This is an example of a balanced force. When the net force is greater than 0 N, the is an unbalanced force.
Answer:
The time taken to reach the maximum height is 3.20 seconds
Explanation:
The given parameters are;
The initial height from which the volcano erupts the lava bomb = 64.4 m
The initial upward velocity of the lava bomb = 31.4 m/s
The acceleration due to gravity, g = 9.8 m/s²
The time it takes the lava bomb to reach its maximum height, t, is given by the following kinematic equation as follows;
v = u - g·t
Where;
v = The final velocity = 0 m/s at maximum height
u = The initial velocity = 31.4 m/s
g = The acceleration due to gravity = 9.8 m/s²
t = The time taken to reach the maximum height
Substituting the values gives;
0 = 31.4 - 9.8 × t
∴ 31.4 = 9.8 × t
t = 31.4/9.8 ≈ 3.204
The time taken to reach the maximum height rounded to three significant figures = t ≈ 3.20 seconds
-- Electric field lines DO never cross. <em>(A)
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-- Electric field lines that are close together DO indicate a stronger electric field. <em>(B)
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-- Electric field lines DO not affect the charge that created them. <em>(C)</em>
-- Electric field lines DON'T begin on north poles and end on south poles. North and South "poles" are the way we talk about magnets, not electric charges.