Answer:
<u>We are given:</u>
displacement (s) = 130 m
acceleration (a) = -5 m/s²
final velocity (v) = 0 m/s [the cars 'stops' in 130 m]
initial velocity (u) = u m/s
<u>Solving for initial velocity:</u>
From the third equation of motion:
v² - u² = 2as
replacing the variables
(0)² - (u)² = 2(-5)(130)
-u² = -1300
u² = 1300
u = √1300
u = 36 m/s
Answer:
1.) U = 39.2 m/s
2.) t = 4s
Explanation: Given that the
height H = 78.4m
The projectile is fired vertically upwards under the acceleration due to gravity g = 9.8 m/s^2
Let's assume that the maximum height = 78.4m. And at maximum height, final velocity V = 0
Velocity of projections can be achieved by using the formula
V^2 = U^2 - 2gH
g will be negative as the object is moving against the gravity
0 = U^2 - 2 × 9.8 × 78.4
U^2 = 1536.64
U = sqrt( 1536.64 )
U = 39.2 m/s
The time it takes to reach its highest point can be calculated by using the formula;
V = U - gt
Where V = 0
Substitute U and t into the formula
0 = 39.2 - 9.8 × t
9.8t = 39.2
t = 39.2/9.8
t = 4 seconds.
Answer:
t = 4.17 hours
Explanation:
given,
The distance between Sun and Neptune, d = 4.5 billion Km
= 4.5 x 10⁹ Km
= 4.5 x 10¹¹ m
The velocity of light, c = 3 x 10⁸ m/s
The velocity is always equal to displacement by the time.
<em>V = d / t m/s</em>
∴ t = d / V
= 4.5 x 10¹¹ m / 3 x 10⁸ m/s
= 15,000 s
= 4.17 h
Hence, the time taken by the light rays to reach the Neptune is, t = 4.17 h
Answer: 
Explanation:
The acceleration of an object can be calculated by using Newton's second law:
where
F is the net force applied on the object
m is the mass of the object
a is its acceleration
In this problem, we have F=125 N and m=25.0 kg, so we can rearrange the equation to calculate the acceleration:
In solids, particles or atom are very closely arranged compared to gasses. When these particles are arranged in such proximity, vibrations from sound are very easily transmitted from one particle to another in the solid. Hence, the sound vibrations can travel through the solid medium more quickly than through a gas medium.
Speed of sound also depends on its frequency and the wavelength.
