In our country, the maximum speed limit is 120km / h. someone is supposed to drive along the straight road at the highest speed, The acceleration of the car when braking is 5m / S2, and the driver's reaction time (from the time when he realizes to stop to operate the brake) is 0.6-0.7s?

In our country, the maximum speed limit is 120km / h. someone is supposed to drive along the straight road at the highest speed, The acceleration of the car when braking is 5m / S2, and the driver's reaction time (from the time when he realizes to stop to operate the brake) is 0.6-0.7s?

The formula s = vt-1 / 2at & # 178;
120 km / h = 100 / 3 M / S
When t = 0.6
S = 100 / 3 × 0.6-1 / 2 × 5 × 0.6-178; = 19.1m
When t = 0.7
S = 100 / 3 × 0.7-1 / 2 × 5 × 0.7-178; = 22.1m
Safe distance 19.1 m to 22.1 M

Everyone's weight on the moon is only one sixth of that on the earth. An astronaut's weight on the earth is 66 kg. How many kg has he lost on the moon?

Mass is conserved and does not change

The top width of the fill slope is 3 meters, the fill height is 5 meters, and the slope is calculated as 1:1.5. What is the volume? How is the calculation formula?

The widening of your subgrade depends on whether it is on both sides or on one side. If it is on one side, v = (3 * 2 + 5 * 1.5) * 5 / 2 * 200 = 6750; if it is on both sides and the width is 1.5m, v = (1.5 * 2 + 5 * 1.5) * 5 * 2 / 2 * 200 = 10500

When an astronaut goes to the moon, her weight is only 1 / 6 of that on the earth. When an astronaut goes to the moon, she has lost 40 kg. So her weight on the earth is several thousand grams?

40*6/5=48kg

If the height and width of a certain earthwork slope are 4m and 2m respectively, the slope is () single choice,
A、1：0.5
B、1：1
C、1：2
D、1：4

The slope of earthwork slope = H / b = 4 / 2 = 2 / 1 = 1 / 0.5 = 1: K, so select a, 1: 0.5, where k is the slope coefficient

The weight of an astronaut on the moon is only one sixth of that on the earth. The weight of an astronaut on the earth is 72 kg. How many kg does he lose on the moon?

Weight = the weight of the body, which is itself a force, in Newtons
And the kilogram is a unit of mass
So weight = 72 kg, which is wrong,
Force = mass? This is the most basic physics concept error
So the problem itself is wrong, completely contrary to physics!

The slope of the foundation pit is 0.8 meters wide, and the slope of the foundation pit is 1.5 meters wide!

How deep is it? What structure is it? Basement? Or ordinary foundation excavation? I can't tell you a formula. S1 is the area of foundation bottom S1 = (length of foundation bottom + working face) * (width of foundation bottom + working face) S2 is the area of foundation top S2 = (length of foundation bottom + working face + height * 0.5 * 2) * (width of foundation bottom + working face + height * 0

The weight of an astronaut on the moon is only 16 times that on the earth. An astronaut weighs 72 kg on the earth. How many kg has he lost on the moon?

72 × 16 = 12 (kg), 72-12 = 60 (kg); a: 60 kg weight loss

The slope is steeper than the rock. The rock is not easy to slide, so it should be safer
For deep cutting and high slope, the unfavorable situation is that the route is parallel to the strike of rock stratum, and the inclination of slope is consistent with that of rock stratum, especially when the inclination of slope is greater than that of rock stratum
The inclination of slope is greater than that of rock stratum. In this sentence, what slope does the inclination of slope refer to, subgrade slope or rock surface slope?

It's too difficult to code on mobile phone. I'll draw a picture for you tomorrow, and I'll see it

A lunar astronaut with a mass of 60 kg can lift a bag of rice weighing 490 n vertically on the earth, so he can lift a mass vertically on the moon
What is the size of the object G = 6 g month

According to g = mg, m month = g / g month = 490N / (1 / 6 * 9.8N / kg) = 300kg