Answer:
C. 441 N
Explanation:
Gravitational force between two objects can by calculated by the formula
= G m₁m₂ / r² , m₁ and m₂ are masses at distance r
= ( 6.67 x 10⁻¹¹ x 45 x 5.98 x 10²⁴) / ( 6.38 x 10⁶ )²
= 44.09 x 10
= 440.9 N
= 441 N .
a). for velocity, you must have a number, a unit, and a direction.
Yes. This one isn't bad. The 'number' and the 'unit' are the speed.
b). the si units for velocity are miles per hour.
No. That's silly.
'miles' is not an SI unit, and 'miles per hour'
is only a speed, not a velocity.
c). the symbol for velocity is .
You can use any symbol you want for velocity, as long as
you make its meaning very clear, so that everybody knows
what symbol you're using for velocity.
But this choice-c is still wrong, because either it's incomplete,
or else it's using 'space' for velocity, which is a very poor symbol.
d). to calculate velocity, divide the displacement by time.
Yes, that's OK, but you have to remember that the displacement
has a direction, and so does the velocity.
Answer:
Explanation:
The total travel time Suzette experiences is the sum of the times in each hallway. Using
time = distance/speed
we can add the times.
(35.0 m)/(3.50 m/s) +(48.0 m)/(1.20 m/s) +(60 m)/(5.0 m/s)
= 10 s + 40 s + 12 s
= 62 s
It takes Suzette 62 seconds to get to class. She does not beat the bell.
Answer:
option A
Explanation:
given,
Kinetic energy of the car = 2000 J
speed of the car is doubled
we know,

........(1)
now, speed of the car is doubled
v' = 2 v


from equation (1)



Hence, the Kinetic energy would be equal to 8000 J.
The correct answer is option A.
Answer:
the final velocity of the wagon is 6 m/s.
Explanation:
Given;
initial velocity of the wagon, u = 4 m/s
mass of the wagon, m = 35 kg
energy applied to the wagon, E = 350 J
The final velocity of the wagon is calculated as;
E = ¹/₂m(v² - u²)

Therefore, the final velocity of the wagon is 6 m/s.