Answer:
ΔR = 5 s
Explanation:
The absolute uncertainty or error in an expression is
ΔR = | | ΔB + | | ΔA
the absolute value guarantees to take the unfavorable case, that is, the maximum error.
We look for the derivatives
= 1
= -1
we substitute
ΔR = 1 ΔB + 1 ΔA
of the data
ΔB = 3 s
ΔA = 2 s
ΔR = 3 + 2
ΔR = 5 s
Answer:
yi = Initial height of the helicopter
yf = final height of the helicopter
vyi = component of the initial vertical velocity of the helicopter
g = gravity constant (9.8m/s^2)
yf = yi + vyideltat - 1/2gt^2
0m = 1000m + (15m/2)deltat - 1/2(9.8m/s^2)t^2
-1000m = (15m/s)t - (-4.9m/s^2)t^2
Use the quadratic formula
4.8t^2 - 15t - 1000 = 0
t1 = 15.75s and t2 = -12.65
t2 is rejected, time can't be negative
Thus, it takes 15.75s before the package strikes the ground.
Momentum refers the amount of motion that a moving object contains. It is calculated from the product of the mass and the velocity of an object. It has SI units of kg-m/s. We calculate as follows:
momentum = mass x velocity
momentum = 0.45 kg x 25 m/s
momentum = 11.25 kg-m/s
Answer:
Explanation:
The weight of the bee is:
with m the mass and g the gravity acceleration.
Electric force of the bee is related with the electric field of earth by:
with q the charge, E the electric field and Fe the electric force.
So:
Because Newton's first law we should make the net force on it equals cero:
with W the weight, Fe the electric force on the bee due earth's electric field and F the force.
So, the applied electric field should be:
The negative sign indicates that the electric field should be opposite to earth's electric field, so it should be upward.