Answer:
90 m
Explanation:
We use an ecuation of uniformly accelerated motion, which allows us to find the distance traveled by the car from the moment that driver applies the brakes until it stops completely, that is, when its final speed is zero.
We isolate the variable d, knowing that the final speed is zero
Answer:
The angle it subtend on the retina is
Explanation:
From the question we are told that
The length of the warbler is
The distance from the binoculars is
The magnification of the binoculars is
Without the 8 X binoculars the angle made with the angular size of the object is mathematically represented as
Now magnification can be represented mathematically as
Where is the angle the image of the warbler subtend on your retina when the binoculars i.e the binoculars zoom.
So
=>
Generally the conversion to degrees can be mathematically evaluated as
Answer:
Speed of the ball relative to the boys: 25 km/h
Speed of the ball relative to a stationary observer: 35 km/h
Explanation:
The RV is travelling at a velocity of
Here we have taken the direction of motion of the RV as positive direction.
The boy sitting near the driver throws the ball back with speed of 25 km/h, so the velocity of the ball in the reference frame of the RV is
with negative sign since it is travelling in the opposite direction relative to the RV. Therefore, this is the velocity measured by every observer in the reference frame of the RV: so the speed measured by the boys is
v = 25 km/h
Instead, a stationary observer outside the RV measures a velocity of the ball given by the algebraic sum of the two velocities:
v = +60 km/h + (-25 km/h) = +35 km/h
So, he/she measures a speed of 35 km/h.