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2 years ago

A cyclist is taking part in the Tour de France, which is a bicycle race that takes place every year.

1 answer:

5 0

Solve the following word problems.
1. The ratio of red marbles and blue marbles that Carlo has is 8: 3. When he
exchanged 35 red marbles for 20 blue marbles from his brother, he was left with
equal number of red and blue marbles.
How many red and blue marbles did he have at the beginning
How many red and blue marbles did he have now

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Find the pressure exerted on the floor by a 100N box whose bottom area is 40cm x 50cm.

Mazyrski [523]

Answer:

Pressure exerted = 500 Pa

Explanation:

The formula for pressure is as follows:

$Pressure = \frac{Force \space\ applied}{Area}$

In this case,

Force applied = 100N

Area = 40cm × 50cm = 2000cm² = 2000 × 10⁻⁴ = 0.2m²

Substituting these values into the formula:

Pressure = $\frac{100}{0.2}$

⇒ Pressure = 500 Pa

3 0

1 year ago

Read 2 more answers

When humans look at the sky, it appears blue, but the Sun appears yellow. What causes this phenomenon?

Lesechka [4]

I believe that the answer is C. The atmosphere scatters blue light more than yellow light.

8 0

3 years ago

Read 2 more answers

Lance Armstrong bikes at a constant speed up the Col d’Izoard, a famous mountain pass. Assume his teammates do such a good job r

svetoff [14.1K]

Work done against gravity to climb upwards is always stored in the form of gravitational potential energy

so we can say

$W = mgh$

here h = vertical height raised

so here we know that

$h = 14.1 sin7.3 km$

here we have

$h = 1.79 km$

now from above equation

$W = (83 kg)(9.81 m/s^2)(1.79 \times 10^3 m)$

$W = 1.46 \times 10^6 J$

so work done will be given by above value

7 0

2 years ago

A 10 kg monkey climbs up a massless rope that runs over a frictionless tree limb and back down to a 15 kg package on the ground.

pshichka [43]

Answer:

A. 4,9 m/s2

B. 2,0 m/s2

C. 120 N

Explanation:

In the image, 1 is going to represent the monkey and 2 is going to be the package. Let a_mín be the minimum acceleration that the monkey should have in the upward direction, so the package is barely lifted. Apply Newton’s second law of motion:

$\sum F_y=m_1*a_m_i_n = T-m_1*g$

If the package is barely lifted, that means that T=m_2*g; then:

$\sum F_y =m_1*a_m_i_n=m_2*g-m_1*g$

Solving the equation for a_mín, we have:

$a_m_i_n=((m_2-m_1)/m_1)*g = ((15kg-10kg)/10kg)*9,8 m/s^2 =4,9 m/s^2$

Once the monkey stops its climb and holds onto the rope, we set the equation of Newton’s second law as it follows:

For the monkey: $\sum F_y = m_1*a \rightarrow T-m_1*g=m_1*a$

For the package: $\sum F_y = m_2*a \rightarrow m_2*g - T = m_2*a$

The acceleration a is the same for both monkey and package, but have opposite directions, this means that when the monkey accelerates upwards, the package does it downwards and vice versa. Therefore, the acceleration a on the equation for the package is negative; however, if we invert the signs on the sum of forces, it has the same effect. To be clearer:

For the package: $\sum F_y = -m_2*a \rightarrow T-m2*g=-m_2*a \rightarrow m_2*g -T=m_2 *a$