Answer:
5.98 m
Explanation:

= 11.15*4.6²/(4π²) = 5.98 m
Answer:
4.8 m/s
Explanation:
When she catches the train,
- They will have travelled the same distance.and
- Their speeds will be equal
The formula for the distance covered by the train is
d = ½at² = ½ × 0.40t² = 0.20t²
The passenger starts running at a constant speed 6 s later, so her formula is
d = v(t - 6.0)
The passenger and the train will have covered the same distance when she has caught it, so
(1) 0.20t² = v(t - 6.0)
The speed of the train is
v = at = 0.40t
The speed of the passenger is v.
(2) 0.40t = v
Substitute (2) into (1)
0.20t² = 0.40t(t - 6.0) = 0.40t² - 2.4 t
Subtract 0.20t² from each side
0.20t² - 2.4t = 0
Factor the quadratic
t(0.20t - 2.4) = 0
Apply the zero-product rule
t =0 0.20t - 2.4 = 0
0.20t = 2.4
(3) t = 12
We reject t = 0 s.
Substitute (3) into (2)
0.40 × 12 = v
v = 4.8 m/s
The slowest constant speed at which she can run and catch the train is 4.8 m/s.
A plot of distance vs time shows that she will catch the train 6 s after starting. Both she and the train will have travelled 28.8 m. Her average speed is 28.8 m/6 s = 4.8 m/s.
Answer:
R = 3.88 m
Explanation:
As the Chinook salmon leaves the water till it gets back into the water it is performing a projectile motion with the following parameters:
V₀ = Launch Speed = 6.7 m/s
θ = Launch Angle = 29°
R= Range of Projectile= Horizontal Distance Covered by Chinook salmon= ?
The value of the range of a projectile is given by the following formula:
R = (V₀² Sin 2θ)/g
R = [(6.7 m/s)² Sin {(2)(29°)}/(9.8 m/s²)]
R = [(6.7 m/s)² Sin (58°)/(9.8 m/s²)]
<u>R = 3.88 m</u>
The formula of density is given by
Density = Mass ÷ Volume
We have:
Mass = 1.989 × 10³⁰ kg
Volume =

=

km³
Density =

=1.13×10¹⁸ kg/km³
Converting 1.13 × 10¹⁸ kg/km³ to g/cm³
1.13 × 10¹⁸ kg = 1.13 × 10¹⁸ × 10³ = 1.13 × 10²¹ grams
1 km³ = 1 × 10⁶ cm³
(1.13 × 10²¹) ÷ 10⁶ = 1.13 × 10¹⁵ gr/cm³
Answer: Density 1.13 × 10¹⁵ gr/cm³