Answer:
The time taken by the rock to reach the ground is 0.569 seconds.
Explanation:
Given that,
A student throws a rock horizontally off a 5.0 m tall building, s = 5 m
The initial speed of the rock, u = 6 m/s
We need to find the time taken by the rock to reach the ground. Using second equation of motion to find it. We get :

So, the time taken by the rock to reach the ground is 0.569 seconds. Hence, this is the required solution.
Answer:
Force between the two charges becomes one fourth of the initial force.
Explanation:
The electrostatic force acting between any two charges is given as,

Here,
F = force
k = Coulomb's constant
= magnitude of charge of the first particle
= magnitude of charge of the second particle
= separation between the two charges
From the above relation,
Thus,



Answer:
9.12267515924 m/s²
Explanation:
Here the moment created by the wheels and the moment created by the center of gravity will balance each other.
h = Height of the center of mass = 78.5 cm
d = Distance from back wheel to the center of mass = 
g = Acceleration due to gravity = 9.81 m/s²
a = Horizontal acceleration
The equation is of the form

The horizontal acceleration of the motorcycle that will make the front wheel rise off the ground is 9.12267515924 m/s²
Answer:
a) 578.0 cm²
b) 25.18 km
Explanation:
We're given the density and mass, so first calculate the volume.
D = M / V
V = M / D
V = (6.740 g) / (19.32 g/cm³)
V = 0.3489 cm³
a) The volume of any uniform flat shape (prism) is the area of the base times the thickness.
V = Ah
A = V / h
A = (0.3489 cm³) / (6.036×10⁻⁴ cm)
A = 578.0 cm²
b) The volume of a cylinder is pi times the square of the radius times the length.
V = πr²h
h = V / (πr²)
h = (0.3489 cm³) / (π (2.100×10⁻⁴ cm)²)
h = 2.518×10⁶ cm
h = 25.18 km
Answer:
0.031 W
Explanation:
The power used is equal to the rate of work done:

where
P is the power
W is the work done
t is the time taken to do the work W
In this problem, we have:
W = 900 J is the work done by the motor
t = 8 h is the time taken
We have to convert the time into SI units; keeping in mind that
1 hour = 3600 s
We have

And therefore, the power used is
