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2 years ago

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A cross country skier moves from location A to location B to location C to location D. Each leg of the back and forth motion tak

es 1 minute to complete; the total time is 3 minutes.
What is the distance travelled by the skier in the first minute?

What is the displacement of the skier in the first minute?

What is the distance travelled by the skier in the first two minutes?

Please help it’ll be greatly appreciated!!

1 answer:

I am Lyosha [343]2 years ago

7 0

Answer:

1. 160

2. 0

3. 120

Explanation:

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Answer:

Independent, dependent, resistance

Explanation:

An independent variable is the one which is varied to test changes in the dependent variable. In the given experiment, voltage is an independent variable is which is being varied and it's effect on current (dependent variable) is being tested. Resistance being held constant.

According to Ohm's Law, current is proportional to voltage.

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2 years ago

Read 2 more answers

An object of mass m moves horizontally, increasing in speed from 0 to v in a time t. The power necessary to accelerate the objec

lana66690 [7]

Answer:

Option e is correct.

Explanation:

An object of mass m moves horizontally, increasing in speed from 0 to v in a time t.

We know that,

Work done = change in kinetic energy

$W=\dfrac{1}{2}m(v^2-u^2)$

Here, u = 0

So,

$W=\dfrac{1}{2}mv^2$

Also,

Power = work done/time

So,

$P=\dfrac{\dfrac{1}{2}mv^2}{t}\\\\=\dfrac{mv^2}{2t}$

So, the correct option is (e).

8 0

2 years ago

A 15g bullet travelling at 100m/s strikes and is absorbed by a 75kg object. Find the speed at which the final object moves.

algol [13]

What i got was
speed of impact that is 44.27 m/s
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2 years ago

If you pull a resistant puppy with its leash in a horizontal direction, it takes 80 N to get it going. You can then keep it movi

netineya [11]

Answer:

The coefficient of static friction between the puppy and the floor is 0.7273.

Explanation:

The horizontal force applied to move the puppy from a steady state has to be greater than the force of static friction, after it is moving the force needs to be equal to be greater than the force of dynamic friction in order to maintain its movement. The force of static friction is given by:

$F_s = \mu_s*N$

Where $F_s$ is the static friction force, $\mu_s$ is the coefficient of static friction and $N$ is the normal force. Since there's no angle on the flor the normal force is equal to the weight of the puppy, therefore, $N = 110\text{ N}$ , to make the puppy moving we need to use a force of 80 N, therefore, $F_s = 80 \text{ N}$ , so we can solve for the coefficient as shown below:

$80 = \mu_s*110\\\mu_s = \frac{80}{110} = 0.7273\\$

The coefficient of static friction between the puppy and the floor is 0.7273.

5 0

2 years ago

A slender rod is 80.0 cm long and has mass 0.370 kg . A small 0.0200-kg sphere is welded to one end of the rod, and a small 0.05

nataly862011 [7]

Answer:

1.10 m/s

Explanation:

Linear speed is given by

$v=r\omega$

Kinetic energy is given by

$KE=0.5I\omega^{2}$

Potential energy

PE= mgh

From the law of conservation of energy, KE=PE hence

$0.5I\omega^{2}=mgh$ where m is mass, I is moment of inertia, $\omega$ is angular velocity, g is acceleration due to gravity and h is height

Substituting m2-m1 for m and 0.5l for h, $\frac {2v}{L}$ for $\omega$ we obtain

$0.5I(\frac {2v}{L})^{2}=0.5Lg(m2-m1)$

$(\frac {2v}{L})^{2}=\frac {gl(m2-m1)}{I}$ and making v the subject

$v^{2}=\frac {gl^{3}(m2-m1)}{4I}$

$v=\sqrt {\frac {gl^{3}(m2-m1)}{4I}}$

For the rod, moment of inertia $I=\frac {ML^{2}}{12}$ and for sphere $I=MR^{2}$ hence substituting 0.5L for R then $I=M(0.5L)^{2}$

For the sphere on the left hand side, moment of inertia I

$I=m1(0.5L)^{2}$ while for the sphere on right hand side, $I=m2(0.5L)^{2}$

The total moment of inertia is therefore given by adding

$I=\frac {ML^{2}}{12}+ m1(0.5L)^{2}+ m2(0.5L)^{2}=\frac {L^{2}(M+3m1+3m2)}{12}$

Substituting $\frac {L^{2}(M+3m1+3m2)}{12}$ for I in the equation $v=\sqrt {\frac {gL^{3}(m2-m1)}{4I}}$

Then we obtain

$v=\sqrt {\frac {gL^{3}(m2-m1)}{4(\frac {L^{2}(M+3m1+3m2)}{12})}}=\sqrt {\frac {3gL^{3}(m2-m1)}{L^{2}(M+3m1+3m2)}}$

This is the expression of linear speed. Substituting values given we get

$v=\sqrt {\frac {3*9.81*0.8^{3}(0.05-0.02)}{0.8^{2}(0.39+3(0.02)+3(0.05))}} \approx 1.08 m/s$

8 0

2 years ago