What makes the planets gravity?

Answer:

B. 1500 kg*m/s

Explanation:

Momentum p = m* v

In any type of collision, the total momentum is preserved!

The total momentum before and the total momentum after the collision is the same. We know the mass and speed after the collision so we can calculate the total momentum.

p1 + p2 =

m1*v1 + m2*v2

m1 = me = 300 kg

v1 = 3 m/s

v2 = 2 m/s

Substitute the given numbers:

300*3 + 300+2

900 + 600

1500 kg*m/s, which is answer B.

Answer:

9.43 m/s

Explanation:

The law of conservation of energy requires that the total energy before and after transformation must be equal. Kinetic energy of car and rocket combined equals the parachute energy and that of car.

Final energy of car will be 66120-36733=29,387 J

Kinetic energy, and making v the subject of the formula then

Where m is the mass and v is velocity.

Substituting 29387 J for KE and 661 kg for m then

A ball is fired with speed v = 180 m/s at an angle 40 degree

So here we can say the components of velocity is given as

now when ball will reach the maximum height its velocity in vertical direction will become zero

so here we can say

now using kinematics we will have

so maximum height is

so it will reach at maximum height of 683 m

Explanation: We use a different element in the chemical equation.

We explain by a example

In this equation, we use the two elements Na and Cl.

Now, we count the number of atoms present on one side 2 atoms of Na and 2 atoms of Cl then the total numbers will be 4 .

But , we use a molecular formula then we count the number of each element of the molecular formula.