Explanation:
a) The Earth makes 1 rotation in 24 hours. In seconds:
24 hr × (3600 s / hr) = 86400 s
b) 1 rotation is 2π radians. So the angular velocity is:
2π rad / 86400 s = 7.27×10⁻⁵ rad/s
c) The earth's linear velocity is the angular velocity times the radius:
40075 km × 7.27×10⁻⁵ rad/s = 2.91 km/s
Answer:
14 m/s
Explanation:
Using the principle of conservation of energy, the potential energy is converted to kinetic energy, assuming any losses.
Kinetic energy is given by ½mv²
Potential energy is given by mgh
Where m is the mass, v is the velocity, g is acceleration due to gravity and h is the height.
Equating kinetic energy to be equal to potential energy then
½mv²=mgh
V
Making v the subject of the formula
v=√(2gh)
Substituting 9.81 m/s² for g and 10 m for h then
v=√(2*9.81*10)=14.0071410359145 m/s
Rounding off, v is approximately 14 m/s
Answer: As with all metals, the alkali metals are malleable, ductile, and are good conductors of heat and electricity. The alkali metals are softer than most other metals.
Alkaline earth metals
The alkaline earth elements are metallic elements found in the second group of the periodic table
Explanation:
Answer:
θ=180°
Explanation:
The problem says that the vector product of A and B is in the +z-direction, and that the vector A is in the -x-direction. Since vector B has no x-component, and is perpendicular to the z-axis (as A and B are both perpendicular to their vector product), vector B has to be in the y-axis.
Using the right hand rule for vector product, we can test the two possible cases:
- If vector B is in the +y-axis, the product AxB should be in the -z-axis. Since it is in the +z-axis, this is not correct.
- If vector B is in the -y-axis, the product AxB should be in the +z-axis. This is the correct option.
Now, the problem says that the angle θ is measured from the +y-direction to the +z-direction. This means that the -y-direction has an angle of 180° (half turn).
Answer is B- 200 m
Given:
m (mass of the car) = 2000 Kg
F = -2000 N
u(initial velocity)= 20 m/s.
v(final velocity)= 0.
Now we know that
<u>F= ma</u>
Where F is the force exerted on the object
m is the mass of the object
a is the acceleration of the object
Substituting the given values
-2000 = 2000 × a
a = -1 m/s∧2
Consider the equation
<u>v=u +at</u>
where v is the initial velocity
u is the initial velocity
a is the acceleration
t is the time
0= 20 -t
t=20 secs
s = ut +1/2(at∧2)
where s is the displacement of the object
u is the initial velocity
t is the time
v is the final velocity
a is the acceleration
s= 20 ×20 +(-1×20×20)/2
<u>s= 200 m</u>
