The main reasons for having few impact craters on Earth compared to moon is due to the presence of atmosphere, water bodies and tectonic activities.
<u>Explanation:</u>
Impact craters are formed on the surface of any object when another very high velocity object hits the surface of the particular object. As force exhibited by any object is directly proportional to the product of mass and acceleration of the object.
In case of moon or other natural satellites, there are no means of reducing the acceleration or mass of the incident high velocity object. But in earth, the presence of different layers of atmosphere causes sufficient friction to reduce the size as well as acceleration of the impeding high velocity object.
Then the presence of larger volume of water bodies on the Earth's surface reduces the chance of hitting on land areas. The third important factor reducing the impact craters are the variation in tectonic plates which helps in keeping only recent impacts on the Earth's surface and erase the old impacts.
So the presence of different layers of atmosphere, water bodies and tectonic plats are the main reasons for having fewer impact craters on Earth compared to the Moon.
Answer: 3.55 s and 0.83 s
Explanation:
The height (in feet) of the softball is given by:
s(t)=-16t²+70t+3
we need to find the time when the ball is 50 feet above the ground:
⇒50 = -16t²+70t+3
we need to solve the quadratic equation
⇒16t²-70t+47 = 0
This gives two values of time: 3.55 s and 0.83 s
I have a hunch that you've got the <em>question</em> totally covered, and what you actually need is the <em>answer.</em>
- Kinetic energy = (1/2) (mass) (speed²)
Multiply each side by 2 : 2 x KE = (mass) ( speed²)
Divide each side by (mass): Speed² = 2 x KE / mass
Square root each side: <em>Speed = √(2 KE/mass)</em>
Look at that ! The question GIVES you the KE and the mass. All you have to do is plug those 2 numbers into the right side of that equation, turn the crank, do the arithmetic, and the speed falls out.
I get 200 m/s . You need to check my work.
(IF that's correct or anywhere close, it's equivalent to something around 447 miles per hour, which is very reasonable for a cruising airliner.)
Explanation:
It is given that,
Earth's magnetic field,
Direction of magnetic field, 67.1 degrees below the horizontal, with the horizontal component directed due north.
The magnetic force on the wire per unit length of wire,
(a) The given scenario is shown in the attached figure as :
Using the right hand rule to find the direction of magnetic force on the wire. By using this rule, we get the magnetic force acting on the wire is in upward direction.
(b) Let I is the current flowing in the wire. The magnetic force is given by the following formula as:
I = 384.61 A
Hence, this is the required solution.