The velocity of a particle is given as v→=-xi^+2yj^-zk^ m/s. The magnitude of acceleration at point (1,2,4) is ______ m/s2. [2026]
(2)
v→=-xi^+2yj^-zk^
∂v→∂t=-∂x∂ti^+2∂y∂tj^-∂z∂tk^
a→=-vxi^+2vyj^-vzk^
a→=xi^+4yj^+zk^
∴ a→ at (1,2,4)=i^+8j^+4k^
|a→|=1+64+16=9
∴ |a→|=9 m/s2