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2 years ago

Help!?

Physics

2 answers:

Marta_Voda [28]2 years ago

3 0

Answer:

7200 m

Explanation:

The pond is 4000 meters away. The woman runs at 2.5 m/s. The time it takes her to reach the pond is:

t = 4000 m / 2.5 m/s

t = 1600 s

The dog is running at 4.5 m/s this entire time. So the distance he runs is:

d = 1600 s × 4.5 m/s

d = 7200 m

olga nikolaevna [1]2 years ago

3 0

Answer:

7200 m

Explanation:

A woman takes her pet dog on a walk to a pond which is 4km away. The woman runs with a speed of 2.5 ms-1 while the dog runs with the speed of 4.5ms^-1 towards the pond and returns to the women and then again runs back to the pond continuously until the woman also manages to reach the pond. The total distance traveled by the dog is 7200 m.

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A 13561 N car traveling at 51.1 km/h rounds

Minchanka [31]

Answer:

a) The centripetal acceleration of the car is 0.68 m/s²

b) The force that maintains circular motion is 940.03 N.

c) The minimum coefficient of static friction between the tires and the road is 0.069.

Explanation:

a) The centripetal acceleration of the car can be found using the following equation:

$a_{c} = \frac{v^{2}}{r}$

Where:

v: is the velocity of the car = 51.1 km/h

r: is the radius = 2.95x10² m

$a_{c} = \frac{(51.1 \frac{km}{h}*\frac{1000 m}{1 km}*\frac{1 h}{3600 s})^{2}}{2.95 \cdot 10^{2} m} = 0.68 m/s^{2}$

Hence, the centripetal acceleration of the car is 0.68 m/s².

b) The force that maintains circular motion is the centripetal force:

$F_{c} = ma_{c}$

Where:

m: is the mass of the car

The mass is given by:

$P = m*g$

Where P is the weight of the car = 13561 N

$m = \frac{P}{g} = \frac{13561 N}{9.81 m/s^{2}} = 1382.4 kg$

Now, the centripetal force is:

$F_{c} = ma_{c} = 1382.4 kg*0.68 m/s^{2} = 940.03 N$

Then, the force that maintains circular motion is 940.03 N.

c) Since the centripetal force is equal to the coefficient of static friction, this can be calculated as follows:

$F_{c} = F_{\mu}$

$F_{c} = \mu N = \mu P$

$\mu = \frac{F_{c}}{P} = \frac{940.03 N}{13561 N} = 0.069$

Therefore, the minimum coefficient of static friction between the tires and the road is 0.069.

I hope it helps you!

3 0

3 years ago

A 2.4 kg block is dropped onto a spring and platform of negligible mass. The block is released

statuscvo [17]

The speed of the block when the compression is 15 cm is 9.85 m/s.

The given parameters;

mass of the block, m = 2.4 kg
height of the block, h = 5 m
compression of the spring, x = 25 cm = 0.25 m

The spring constant is calculated as follows;

$F = kx\\\\mg = kx\\\\k = \frac{mg}{x} \\\\k = \frac{2.4 \times 9.8}{0.25} \\\\k = 94.08 \ N/m$

The speed of the block when the compression is 15 cm can be determined by applying the principle of conservation of energy;

$\Delta K.E = \Delta P.E\\\\\frac{1}{2} m(v^2 - v_{0 }^2 ) = mgh - \frac{1}{2} kx^2\\\\\frac{1}{2} mv^2 = mgh - \frac{1}{2} kx^2\\\\mv^2 = 2mgh - kx^2\\\\v^2 = \frac{2mgh - kx^2}{m} \\\\v = \sqrt{\frac{2mgh - kx^2}{m}} \\\\v = \sqrt{\frac{(2 \times 2.4 \times 9.8 \times 5) - (94.08 \times 0.15^2)}{2.4}} \\\\v = 9.85 \ m/s$

Thus, the speed of the block when the compression is 15 cm is 9.85 m/s.

Learn more here:brainly.com/question/14289286

8 0

2 years ago

What type of lens is used to make objects appear smaller and clearer convex or concave?

GalinKa [24]

The answer is Concave lenses

5 0

2 years ago

Carmen is helping load furniture and boxes onto a moving truck. She picks up boxes of her things, places them on a cart, and pus

SpyIntel [72]

Answer:

friction is the force she is useing

7 0

3 years ago

Calculate the acceleration of a bottle rocket that is traveling at a speed of 74 m/s, and then descends at a speed of 89 m/s. It

Harlamova29_29 [7]

Answer:Falling objects form an interesting class of motion problems. For example, we can estimate the depth of a vertical mine shaft by dropping a rock into it and listening for the rock to hit the bottom. By applying the kinematics developed so far to falling objects, we can examine some interesting situations and learn much about gravity in the process.

Explanation:

5 0

2 years ago