Answer:
Approximately
, assuming friction between the vehicle and the ground is negligible.
Explanation:
Let
denote the mass of the vehicle. Let
denote the initial velocity of the vehicle. Let
denote the spring constant (needs to be found.) Let
denote the maximum displacement of the spring.
Convert velocity of the vehicle to standard units (meters per second):
.
Initial kinetic energy (
) of the vehicle:
.
When the vehicle is brought to a rest, the elastic potential energy (
) stored in the spring would be:
.
By the conservation of energy, if the friction between the vehicle and the ground is negligible, the initial
of the vehicle should be equal to the
of the vehicle. In other words:
.
Rearrange this equation to find an expression for
, the spring constant:
.
Substitute in the given values
,
, and
:

Answer:
(A) ratio of electric force to weight will be 
(b) Electric field will be 
Explanation:
We have given mass of bee = 100 mg = 
Charge on bee 
Electric field E = 100 N/C
Weight of the bee 
Electric force on the bee 
So the ratio of electric force on the bee and weight is 
(B) To hold the bee in air electric force must be equal to weight of bee
So 


Answer:
(A) Impulse = 9Ns
(B) F = 1286N
Explanation:
Impulse = change in momentum = m(v-u)
v = 0 (the hand comes to a stop)
u = -10m/s
Mass = 0.9kg
Impulse = 0.9 ×(0- (-10))
= 9Ns
(B) F×t = Impulse
F = Impulse/ t
t = 7ms = 7×10-³
F = 9/ (7×10-³)
F = 1286N.
Recuerda que distancia=velocidad x tiempo (

). vamos a llamar

a la distancia que reccore el primer bus, y

la distancia que recoore el segundo. Los se econtraran cuando la ditancia recorrida por cada bus sea la misma, es decir

.
Ahora sabemos que la velocidad del primer bus es 30 km/h y su tiempo es

; en cuanto al segundo bus, su velocidad es 45 km/h y como sale 2 horas mas tarde su tiempo será

. Ahora podemos reemplazar los valores en nuestra ecuación de de distanica para hallar el tiempo:





Los buses se encontraran en 6 horas, 4 horas después de haber salido el segundo bus. Ahora para hallar la distancia a la que los buses estaran de <span>san vicente del caguan solo necesitaremos reemplazar la el tiempo en nuestra equación de distancia para el primer bus:
</span>


<span>
En el punto de encuentro los buses estarán a 180 km de San Vicente del Caguan.</span>