Answer:
The velocity of the boat with respect to the ground is 3 km/h
Explanation:
The speed of an object is different depending on the reference system you use. This is called relative speed.
A boat travels upstream, this means that it moves in the opposite direction to the river current.
A boat travels upstream, this means that it moves in the opposite direction to the river current. Then, if the boat moves in the positive direction of the x axis at 10 km / h with respect to the water of a river, the water flows in the negative direction of the x axis at 7 km / h with respect to the ground.
This causes the speed of the boat relative to the ground to be calculated as follows:
<em>VbG = Vbw - VwG
</em>
where VbG is the speed of the boat relative to the ground, Vbw is the speed of the boat relative to the water of the river and VwG is the speed of the water relative to the ground.
So: VbG=10 km/h – 7 km/h
<u><em>VbG= 3 km/h
</em></u>
The direction of this velocity is in the positive x-direction.
D.) Distance travelled / time ...........
a). Perihelion . . . the point in Earth's orbit that's closest to the Sun.
We pass it every year early in January.
b). Aphelion . . . the point in Earth's orbit that's farthest from the Sun.
We pass it every year early in July.
c). Proxihelion . . . a made-up, meaningless word
d). Equinox . . . the points on the map of the stars where the Sun
appears to be on March 21 and September 21.
Answer:
F = 1400 N
Explanation:
It is given that,
Mass of the ball, m = 70 kg
It is moving with an acceleration of 20 m/s². We need to find the force exerted by the ball.
Force is given by the product of mass and acceleration. So,
F = ma

So, the force of 1400 N is exerted by a metal ball.