We can use the equation of motion:
s = ut + 1/2 x at²
Both the velocity and acceleration are downwards so we'll consider the downward direction positive
30 = 8t + 4.91t²
4.91t² + 8t - 30 = 0
Solving the quadratic:
t = 1.79 s; t = -3.42 s
Negative time is not possible so second value discarded. Time taken = 1.79 seconds
750W 30mins...750x30x60 joules ... 75000x18 ... about 1,500,000j
D
Answer:
Quark
Explanation:
In the past the proton,neutron and electron were believed to be indivisible. Quarks were later discovered to be particles that make up the proton and neutron. Quarks are known as fast moving points of energy and are usually joined to one another through gluons. Neutron has two down quarks and one up quark while proton has two up quarks and one down quark.
Answer:
u = 8.3 x 10⁻⁴ m/s
Volume to Pass = 5 x 10⁻⁴ L = 0.5 mL
Explanation:
First we find area of pipe:
A = πd²/4
A = π(2.54 x 10⁻² m)²/4
A = 0.02 m²
Now,
Q = (1 L/min)(1 min/60 s)(0.001 m³/1 L)
Q = 1.66 x 10⁻⁵ m³/s
Therefore,
u = Q/A
u = (1.66 x 10⁻⁵ m³/s)/(0.02 m²)
<u>u = 8.3 x 10⁻⁴ m/s</u>
Time for 10 mL:
T = 0.01 L/Q
T = (0.01 L)/(1 L/min)
T = (0.01 min)(60 s/1 min)
T = 0.6 s
Liters of water to pass:
Volume to Pass = uT
Volume to Pass = (8.3 x 10⁻⁴ m/s)(0.6 s)
<u>Volume to Pass = 5 x 10⁻⁴ L = 0.5 mL</u>