The time after being ejected is the boulder moving at a speed 20.7 m/s upward is 2.0204 s.
<h3>What is the time after being ejected is the boulder moving at a speed 20.7 m/s upward?</h3>
The motion of the boulder is a uniformly accelerated motion, with constant acceleration
a = g = -9.8 
downward (acceleration due to gravity).
By using Suvat equation:
v = u + at
where: v is the velocity at time t
u = 40.0 m/s is the initial velocity
a = g = -9.8 
is the acceleration
To find the time t at which the velocity is v = 20.7 m/s
Therefore,
The time after being ejected is the boulder moving at a speed 20.7 m/s upward is 2.0204 s.
The complete question is:
A large boulder is ejected vertically upward from a volcano with an initial speed of 40.0 m/s. Ignore air resistance. At what time after being ejected is the boulder moving at 20.7 m/s upward?
To learn more about uniformly accelerated motion refer to:
brainly.com/question/14669575
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A single polarizer will stop 50% of the incoming light.
the answer is heat engine
Answer:
you count the squares or messure it
Explanation:
you can raw equal squares about 1 cm wide if possible all equal and count the squares eg theres 10 squares (small hand) so that would be 10cm squared
(a) The net force on the shopping cart is zero.
(b) The the force of friction on the shopping cart is 25 N.
(c) When same force is applied to the shopping cart on a wet surface, it will move faster.
<h3>Net force on the shopping cart</h3>
The net force on the shopping cart is calculated as follows;
F(net) = F - Ff
where;
- F is the applied force
- Ff is the frictional force
ma = F - Ff
where;
- a is acceleration of the cart
- m is mass of the cart
at a constant velocity, a = 0
0 = F - Ff
F(net) = 0
F = Ff = 25 N
Net force is zero, and frictional force is equal to applied force.
<h3>On wet surface</h3>
Coefficient of kinetic friction of solid surface is greater than that of wet surface.
Since frictional force limit motion, when the frictional force is smaller, the object tends to move faster.
Thus, the cart will move faster on a wet surface due to decrease in friction.
Learn more about frictional force here: brainly.com/question/24386803
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