<span>they took advantage of innovations in sailing technolgy that allowed ships such as the caravel to sail against the wind.</span>
Answer: The question is incomplete or some details are missing. Here is the complete question ; (a) The driver of a car slams on the brakes when he sees a tree blocking the road. The car slows uniformly with acceleration of −5.55 m/s2 for 4.05 s, making straight skid marks 63.0 m long, all the way to the tree. With what speed (in m/s) does the car then strike the tree? m/s
(b) What If? If the car has the same initial velocity, and if the driver slams on the brakes at the same distance from the tree, then what would the acceleration need to be (in m/s2) so that the car narrowly avoids a collision? m/s2
a ) With what speed (in m/s) does the car then strike the tree? m/s = 4.3125m/s
b) then what would the acceleration need to be (in m/s2) so that the car narrowly avoids a collision? m/s2 = -5.696m/s2
Explanation:
The detailed steps and calculation is as shown in the attached file.
You haven't stated any numbers showing that the intensity of solar radiation at the surface is lower than at the top of the atmosphere. Your data only show that the value at the top of the atmosphere is different on different dates.
From our vast experience, however, we do know that the solar intensity at the surface IS lower than it is at the top of the atmosphere, simply because the atmosphere absorbs some solar radiation ... different amounts of it at different wavelengths.
That's the main reason, for example, why the sky is red at sunrise and sunset and blue the rest of the day, and why the temperature of the air is so much higher than 3° absolute, and why we aren't broiled by X-rays all day. Also the reason why it's worth the tremendous cost and makes such a difference to build astronomical observatories on mountain tops and in low-Earth-orbit, instead of in convenient deep valleys.
1. Protons and Neutrons
2.Inside nucleus
3. Covalent and chemical bonds?
I’m not sure about 3 but other 2 are right lol
Answer:
Minimum coefficient of kinetic friction between the surface and the block is
.
Explanation:
Given:
Mass of the block = M
Spring constant = k
Distance pulled = x
According to the question:
<em>We have to find the minimum co-efficient of kinetic friction between the surface and the block that will prevent the block from returning to its equilibrium with non-zero speed. </em>
So,
From the FBD we can say that:
⇒ Normal force,
<em>...equation(i)</em>
⇒ Elastic potential energy,
=
<em> ...equation (ii)</em>
⇒ Frictional force,
=
<em> ...equation (iii)</em>
⇒ Plugging (i) in (iii).
⇒
Now,
⇒ As we know that the energy lost due to friction is equivalent to PE .
⇒
<em>...considering PE as</em>
or
.
Arranging the equation.
⇒ 
⇒
<em>...eliminating x from both sides.</em>
⇒
<em>...dividing both sides wit Mg.</em>
Minimum coefficient of kinetic friction between the surface and the block is
.