Answer:
V4=9.197v
Explanation:
Given:
V1= 18v ,V2= 12v ,r1=r5=58ohms ,r2=r6=124ohms , r3=47ohms ,r4= 125ohms
V4= I4R4 = V2/(R4 + R5)×R4
V4= 12×125 /(125 + 58)
V4=1500/183 =9.197v
Answer:
From lowest to highest acceleration:
3rd train
2nd train
1st train
Explanation:
The acceleration of an object can be found by using Newton's second law:
where
a is the acceleration
F is the net force on the object
m is the mass of the object
We notice that for equal values of the forces F, the acceleration a is inversely proportional to the mass, m. Therefore, greater mass means lower acceleration, and viceversa.
So, the train with lowest acceleration is the one with largest mass, i.e. the 3rd train consisting of 50 equally loaded freight cars. Then, the 2nd train has larger acceleration, since it consists of 50 empty freight cars (so its mass is smaller). Finally, the 1st train (a single empty car) is the one with largest acceleration, since it is the train with smallest mass.
Answer:
Wolves are a keystone species because they are so important to the ecosystem that their removal causes a catastrophic disequilibrium.
Explanation:
Wolves are the predators available in the environment but they exist in relatively less number while comparing it with another species of animals. Wolves influence their pray which are influenced by plants. Thus, They are so important to the ecosystem that their removal causes a catastrophic disequilibrium.
Answer:
the normal force on the rock acts perpendicular to the bowl's surface.
Explanation:
As we know that Normal force is the reaction force of two contact surfaces which always act perpendicular to the contact surfaces
Here we know that the rock is moving inside the bowl
So Normal force on the rock must perpendicular to the surface of the bowl which always passes through the center of the bowl.
Since the rock is moving in vertical plane so it must have two acceleration
1) Tangential acceleration which will increase the magnitude of the speed along the tangential path
2) Centripetal acceleration which will change the direction of the rock
So here only correct option will be
the normal force on the rock acts perpendicular to the bowl's surface.
The equatorial radius of the earth is
r = 6378 km = 6378 x 10³ m
The earth makes 1 revolution in 24 hours.
The angular velocity is
ω = (2π rad)/(24*3600 s) = 7.2722 x 10⁻⁵ rad/s
The tangential velocity (linear velocity) at a point on the equator is
v = rω
= (6378 x 10³ m)*(7.2722 x 10⁻⁵ rad/s)
= 463.8 m/s
Answer: 463.8 m/s
