Answer:
Lindsey biked 45 miles for 3 hours at 15 mph and walked 8 miles for 2 hours at 4 mph.
Explanation:
Speed = distance/time
Let the distance that Lindsey biked through be x miles and the time it took her to bike through that distance be t hours
Then, the rest of the distance that she walked is (53 - x) miles
And the time she spent walking that distance = (5 - t) hours
Her biking speed = 15 mph = 15 miles/hour
Speed = distance/time
15 = x/t
x = 15 t (eqn 1)
Her walking speed = 4 mph = 4 miles/hour
4 = (53 - x)/(5 - t)
53 - x = 4 (5 - t)
53 - x = 20 - 4t (eqn 2)
Substitute for X in (eqn 2)
53 - 15t = 20 - 4t
15t - 4t = 53 - 20
11t = 33
t = 3 hours
x = 15t = 15 × 3 = 45 miles.
(53 - x) = 53 - 45 = 8 miles
(5 - t) = 5 - 3 = 2 hours
So, it becomes evident that Lindsey biked 45 miles for 3 hours at 15 mph and walked 8 miles for 2 hours at 4 mph.
Answer:
The only liquid elements at standard temperature and pressure are bromine (Br) and mercury (Hg).
Answer:
36,67 degrees Celsius
Explanation:
The simplest way to approach this problem, given the information provided, is to simply start with the speed difference.
Goal: 353 m/s
Start: 343 m/s (at 20 degrees Celsius).
Difference: 10 m/s
Variation rate: 0.60 m/s/d (d = degree)
So, 16,67 degrees more than the starting point.
The temperature will then be 36.67 degrees Celsius, when the sound travels at the speed of 353 m/s.
Answer:
r = 2.031 x 10⁶ m = 2031 km
Explanation:
In order for the asteroid to orbit the planet, the centripetal force must be equal to the gravitational force between asteroid and planet:
Centripetal Force = Gravitational Force
mv²/r = GmM/r²
v² = GM/r
r = GM/v²
where,
r = radial distance = ?
G = Universal Gravitational Constant = 6.67 x 10⁻¹¹ N.m²/kg²
M = Mass of Planet = 3.52 x 10¹³ kg
v = tangential speed = 0.034 m/s
Therefore,
r = (6.67 x 10⁻¹¹ N.m²/kg²)(3.52 x 10¹³ kg)/(0.034 m/s)²
<u>r = 2.031 x 10⁶ m = 2031 km</u>
Answer:
80×5×10=4000J
so therefore, work done on the body is 4000J
