Answer:
A) 
B) 
Explanation:
A) In this situation we are talking about a car moving only in the X- axis, hence the velocity of the car is:

Where the unit vectors
,
and
represent the components
,
and
in the cartesian plane.
In this sense, each unit vector is defined to have a magnitude of exactly one (1).
B) Velocity is defined as the variation of position in time, if this car is moving only along the x direction we will have:

Clearing the position:



The city monitors the steady rise of CO from various sources annually. In the year "C: 2019"<span> (rounded off to the nearest integer) will the CO level exceed the permissible limit.
If this isn't the answer, let me know and i'll figure out what it is. But I believe this is it. :) </span>
Answer:
Explanation:
a )
one kg of coal gives energy of 27 x 10⁶ J
75 kg of coal gives energy of 27 x 10⁶ x 75 J
So rate which energy is coming out of coal per second
= 27 x 10⁶ x 75 J
= 2025 x 10⁶ J /s
2025 million watts .
b ) energy output = 800 million watts
efficiency = (800 / 2025) x 100
= 39.5 % .
Coefficient of static friction = tan(a) = 0.4
r = 740 m
g = 9.8 m/s²

v = √(9.8 × 740 × 0.4) m/s
v ≈ 53.85908 m/s
In collision that are categorized as elastic, the total kinetic energy of the system is preserved such that,
KE1 = KE2
The kinetic energy of the system before the collision is solved below.
KE1 = (0.5)(25)(20)² + (0.5)(10g)(15)²
KE1 = 6125 g cm²/s²
This value should also be equal to KE2, which can be calculated using the conditions after the collision.
KE2 = 6125 g cm²/s² = (0.5)(10)(22.1)² + (0.5)(25)(x²)
The value of x from the equation is 17.16 cm/s.
Hence, the answer is 17.16 cm/s.