Calculate the average speed (in km/hr) of Charlie whonruns to the store 4 km away in 30 minutes

Somatic motor neurons originate in the central nervous system, project their axons to skeletal muscles (such as the muscles of the limbs, abdominal, and intercostal muscles), which are involved in locomotion.

Explanation:

Muscles move on commands from the brain. Single nerve cells in the spinal cord, called motor neurons, are the only way the brain connects to muscles. When a motor neuron inside the spinal cord fires, an impulse goes out from it to the muscles on a long, very thin extension of that single cell called an axon.

4 0

2 years ago

A 30 g horizontal metal bar, 13 cm long, is free to slide up and down between two tall, vertical metal rods that are 13 cm apart

natita [175]

Answer:

Terminal speed, v = 6901.07 m/s

Explanation:

It is given that,

Mass of the horizontal bar, m = 30 g = 0.03 kg

Length of the bar, l = 13 cm = 0.13 m

Magnetic field, $B=5.5\times 10^{-2}\ T$

Resistance, R = 1.2 ohms

We need to find the terminal speed oat which the bar falls. When terminal speed is reached,

Force of gravity = magnetic force

$mg=ilB$ ..................(1)

i is the current flowing

l is the length of the rod

Due to the motion in rods, an emf is induced in the coil which is given by :

$E=Blv$ , v is the speed of the bar

$iR=Blv$

$i=\dfrac{Blv}{R}$

Equation (1) becomes,

$mg=\dfrac{B^2l^2v}{R}$

$v=\dfrac{mgR}{B^2l^2}$

$v=\dfrac{0.03\times 9.8\times 1.2}{(5.5\times 10^{-2})^2(0.13)^2}$

v = 6901.07 m/s

So, the terminal speed at which the bar falls is 6901.07 m/s. Hence, this is the required solution.

5 0

2 years ago

An object is pulled up an incline plane at a constant velocity as the picture above shows. Calculate the tension on the rope.

WARRIOR [948]

Hi there!

$\large\boxed{545N}$

Since the object is being pulled at a constant velocity, the forces must be balanced.

Since there is no movement vertically, we must take into account the horizontal forces. We can also assume a positive acceleration to be in the direction of motion.

The acceleration and force due to gravity on an incline is:

a = gsinФ

F = MgsinФ

∑F = -MgsinФ + T

Since it is getting pulled at a constant velocity, ∑F = 0. So:

0 = -MgsinФ + T

MgsinФ = T

Solve for T by plugging in values. Let g = 10 m/s²

T = (120)(10)sin(27) ≈ 545 N

6 0

3 years ago