B. Earth’s outer surface is cooler than its interior layers.
Explanation:
- The option given above is showing us that the temperature in the interior of the earth is higher than the temperature in the outer layer.
- There is travel of heat from the inner core of the earth to the earth's crust. Due to the loss of heat when it reaches the outer layer, there arises a temperature difference.
- The heat loss is due to the absorption of heat during its transfer. Hence, option B is the answer.
A mechanical wave can only travel through matter.
Answer:
Explanation:
Given that,
Initial Angular velocity w=500rpm
Converting from rpm to rad/s
1rev =2πrad
1minutes =60secs
500rpm=500rev/mins
w = 500×2π/60
wi=52.36rad/s
The final angular velocity wf=0rad/s
Time to stop is t=2.6sec
We want to find angular acceleration α
Using the equation of angular motion
wf = wi + αt.
0 = 52.36 + 2.6α
-52.36=2.6α
α = -52.36/2.6
α = -20.14rad/s²
The angular acceleration is negative because it is decelerating.
Then, α=20.14rad/s²
Cerebrospinal fluid or Hydrocephalus
Answer:
ΔP = 14.5 Ns
I = 14.5 Ns
ΔF = 5.8 x 10³ N = 5.8 KN
Explanation:
The mass of the ball is given as 0.145 kg in the complete question. So, the change in momentum will be:
ΔP = mv₂ - mv₁
ΔP = m(v₂ - v₁)
where,
ΔP = Change in Momentum = ?
m = mass of ball = 0.145 kg
v₂ = velocity of batted ball = 55.5 m/s
v₁ = velocity of pitched ball = - 44.5 m/s (due to opposite direction)
Therefore,
ΔP = (0.145 kg)(55.5 m/s + 44.5 m/s)
<u>ΔP = 14.5 Ns</u>
The impulse applied to a body is equal to the change in its momentum. Therefore,
Impulse = I = ΔP
<u>I = 14.5 Ns</u>
the average force can be found as:
I = ΔF*t
ΔF = I/t
where,
ΔF = Average Force = ?
t = time of contact = 2.5 ms = 2.5 x 10⁻³ s
Therefore,
ΔF = 14.5 N.s/(2.5 x 10⁻³ s)
<u>ΔF = 5.8 x 10³ N = 5.8 KN</u>
